TW: Gaslighting, Emotional Manipulation, Forced Assisted Suicide. For those of you who don't want to read that kind of subject matter, you can message me (if you're comfortable) and I'll tell you what happens in the chapter instead. Happy reading.

On an unrelated note, I just want to say that I love my Mum. She helped edit nearly all of Kalliopê, and she rocks.

Mari tore her eyes open and groaned. She was in a tunnel with shiny tiled walls. The labyrinth. Why was she back in the labyrinth? Her head felt as if it had been peeled open like an orange and her brain had been all mushed around. She tapped her fingers to her forehead and was met with rough fabric. A bandage. What happened? The last thing she remembered was talking to Naomi, and then...

She shot up, looking around.

"Hello, Frankie."

Mason was sitting on the other side of the corridor, twirling Drys around his left hand. "This is very pretty. Didn't Oak give it to you? Oak was always good. Much better than Thistle, who let you die. Don't worry, you don't have to be scared of Thistle anymore. And I'll give this back to you, when I can know for sure that you won't try to hurt me with it."

Mari wondered if she was supposed to feel happy he was here. All she'd wanted last winter was the chance to talk to him. To explain what Luke had done. That had blown up in her face, but Mari would have sold her sketchbook for a single rusty penny if it meant she could talk to Mason last winter. But now all she could feel was tired. Of all of this. Of him. Of herself, maybe. And when she opened her mouth, it wasn't to talk about what Luke had done, or what could have made Adela hate Mason so much.

"How did you find me?" Mari asked. "What did you do to Naomi?"

"Naomi this, Naomi that," Mason sneered. "Stop talking about her. She never should have gotten involved. I promise you, she doesn't give a crap about what happens to you. She's probably glad you're here, and she doesn't have to worry about you bothering her anymore."

Mari looked down at her lap. He wasn't right, was he? Naomi had said she cared about Mari. She'd said it a whole bunch of times. Naomi had let Mari stay with her. She'd spent time with Mari. Actual, meaningful time. When she really didn't have to and Mari would have been just fine on her own. Naomi had stayed with her anyway, and was nice. But what if Mari was wrong? Maybe Naomi was just being polite. Mari was Will's sister, after all. Naomi would be nice to her son's sister. Was that all it was?

"I- people care about me, Mason." Mari wrapped her arms around herself, looking away.

"Of course they do," Mason agreed. "I care about you, Frankie. Now." He pulled Mari to her feet and brushed off her shoulders. "You feeling alright? The head doesn't hurt too much, does it? I don't know how long we're going to be walking."

Without waiting for an answer, he clamped an arm around Mari's upper back and began to walk, dragging her with him. It almost reminded her of how Lee would sling his arm over her shoulders during Capture the Flag. But that always made her happy. This made her feel trapped.

"Stop calling me that!" Mari snapped. "Please, stop calling me that."

Mason walked on as if he hadn't heard her. "If your so-called friends cared about you so much, then wouldn't they be honest with you? I heard what you were saying to that Naomi woman in the Iris-message, Frankie. You had no idea where I was, did you? Or you would have been running out of there with all of your little friends. You thought I was on the Princess Andromeda the whole time. But I was in Texas. And your idiot brother and your little death-spreader friend-"

"Hey!" Mari glared at Mason, anger boiling up in her gut. Adela was not some kind of walking disease, she was a person. A really, really good person who didn't deserve the hand she'd been dealt by the fates and definitely didn't deserve to be insulted about it. "Say what you want about me but don't call Adela things like that! She's not... she's good, but even if she wasn't good, nobody deserves to be called that! And whilst we're on the subject of insulting people I happen to care about, Will is your brother, too!"

"It's sweet that you're defending them, Frankie. Really. You were always sweet when we were little." Mason smiled at her. "But they don't deserve it. They knew I was in Texas, didn't you know that? If they cared about you, even at all, then wouldn't they have told you? I would have told you, Frankie. But they didn't. I heard you talking to that woman. You didn't even know."

"You're lying," Mari said. "They wouldn't keep that from me. They wouldn't!"

"They did. Come on. You never once thought either of them was hiding something?"

Something flashed in the back of Mari's mind. Adela had been in Texas. She'd been outside that Spanish restaurant, a week before Mari and Will went back to camp. And Will... he'd been missing. And he hadn't said anything about where he'd been. Mari hadn't thought either of them would. Because they both cared enough not to. People cared about her. Right?

Mason took her silence as an answer, and pulled her forwards again. She looked at the side of his face. He was grinning. "Don't worry, Frankie. You still have me. I wouldn't lie to you."

"Why were you in Texas?"

Mason's face froze. "I was... taking care of business for Luke."

"You hesitated."

"No, I didn't. You're imagining things. Come on, speed up. I don't want to be in this maze any longer than I have to, and I can't imagine you do, either."

Mari dug her heels into the ground, hoping that would be enough to slow Mason down. It wasn't. He just huffed and dragged her harder. "I understand if you're angry at me," he told her. "I did get you killed. I know I have a lot to make up for. If it's any consolation, I wish Thistle had thrown me out of the car instead. That's what Mom would have wanted. She- she asked me to protect you. All she ever wanted was for you to be safe. Thistle made me fail, in everything."

"Mason..." Mari trailed off. "Did you ever think that maybe your mum shouldn't have done that?"

"What do you mean?" Mason turned towards her again, his eyes bloodshot.

"I- I saw all the memories you forced me to see. You know that, right?" Mason nodded, so Mari continued. "You were a kid, Mason. Just a really little kid. No kid should have the burden of protecting an entire person. Frankie's death... it wasn't your fault."

"Yes, it was!" Mason's lips pulled back into a snarl. "I was a horrible brother, Frankie, but I'm trying to be better! Why won't you let me?"

"Because I'm not Frankie!" Mari snapped. "I'm not her. I don't want you to keep calling me that name and I'm not joining Kronos with you!"

Mason stopped walking.

His eyes went wide and his lips trembled. Mari thought for a second that he was going to start crying, which would have been even worse than him yelling, because if Mason started crying then Mari might cry, too. But a harsh, hacking cough came from his throat and Mari realised with dull horror that he was laughing. Mason cackled like a witch out of a storybook, head whipping back and fourth. When he finally looked at Mari again, his eyes weren't just bloodshot, they were completely vacant.

"Mason...?"

"You're in denial, Frankie," he told her. "You want to pretend to be someone else? Fine. I'll put up with that until you accept reality. But you are joining Kronos. You should be angry at the gods. You should be angrier than I ever was. I begged our father to save you and he let you die. The gods let you rot on Circe's island for five years but you still defend them. Why?!"

Mari looked down. So that was what Mason thought. Luke hadn't even bothered to give him a properly thought-out excuse. He'd just blamed it on the gods. And it probably worked because the gods had already messed up so many things in Mason's life. What was one more on the list? Was there even a chance he'd come back to camp after all that? She would definitely try to convince him, even now, but a small part of her wasn't sure she wanted him there. But surely, if she told him what Luke had done, he wouldn't return to The Princess Andromeda either, right?

"Mason-"

Mari opened her mouth to tell him, but before she could get more than a word out, her throat started clogging up. She clutched her neck, hacking out a cough. Mason grabbed her shoulders, and slapped her on the back, looking worried. "What's wrong? Are you okay?"

Mari heaved. She couldn't form a response because her throat felt full of churning cement. Her body tipped forward and she coughed. She was used to this - it was probably blood. On Circe's island, she'd coughed up blood all the time. But why would she be doing it now? She'd used the mist more than usual since entering the labyrinth, sure, but she wasn't so weak that it was causing this... right? The coughs finally subsided and she opened her eyes.

Dirt.

It was dirt.

Why was she coughing up dirt?

"What's happening, Frankie?" Mason asked her.

Mari shook her head. "I don't know. Listen, when I went miss-"

Mari didn't get to finish because her throat was clogging again. She coughed up another pile of mud, this one tinged slightly red. Mari swallowed and nearly gagged - her mouth tasted like earthworms.

"Lu-" Mari tried again. "He-"

Her throat went cement-y again, and she vomited another pile of dirt. Her knees went lax, nearly sending her crashing to the floor. Mason caught her before she could. What was happening? Every time she tried to tell Mason that Luke had kidnapped her, it felt like her throat was cosplaying as a plant bed. Wait... every time she tried to tell Mason that Luke had kidnapped her...

That was the problem. She couldn't tell Mason about what Luke had done. Not if she wanted to keep her vocal chords intact. Or just keep them in general.

Mason hauled her up again till her legs were stabilised. "Frankie, stop talking. It's hurting you."

"I'm... not... Frankie..." Mari wheezed.

"Lu..." Mason mused. "You tried to say Luke, right? You said it on Mount Tam, too. I get it, you're scared of him. Half the camp is, but he's not a bad guy. He's been a really, really good friend to me. He promised me that he'd make sure you're not hurt, no matter which side you're on. Then, after Kronos wins, he'll make sure we can leave all this behind. Forget about there ever being gods, or titans. We can live our lives free from all of it, be siblings again. He promised to protect us, Frankie."

Mari shook her head, covering her mouth. She wanted to tell Mason about what Luke had done. She wanted to scream it to the world, even if the world didn't care. But she couldn't. She could almost feel the dirt coating her oesophagus again at the thought. So, she focused on something else to try and convince Mason.

"I don't want to go with you. If that's why you joined Luke, then it's pointless because I won't ever be happy like that, and I won't go live with you. So, please," Mari begged. "Come back to camp."

"You don't know what you're saying." Mason shook his head. "I have everything planned. When Luke wins - when Kronos wins - he'll open up the underworld. The dead will walk the earth again. That includes our Mom. Luke bought an apartment for us, right above where we used to live. Our Mom can come back, Frankie. I can make things right for letting you die and we can all live together again. Don't you want that? To see our Mom again?"

"Mason..." Mari trailed off. "I don't know that woman, but she's not my Mum. I- I don't have a Mum. Whoever she is, she gave up when I was a baby. I'm Mari. I'm not Frankie. Maybe I used to be, I don't know, but I'm not her today. Please, stop trying to make me be Frankie. I'm sorry she died and I'm sorry I'm not her, but you can't... I don't think she'd want you to do this."

"I am this." Mason started walking again. His steps were shaky, but Mari was still pulled along with him. "And so are you, whether you like it or not."

Mari's breath hitched. She shook her head and her eyes went watery. She blinked four times but Mason didn't seem to notice. He just kept talking, and talking, and every word he said made Mari feel he was trying to take a giant rubber and erase her entire... everything...

"I'm just asking you to be who you are. That's never a bad thing, Frankie. And who you are is my sister. You don't need to cling to someone else's identity anymore. You can just be Frankie. Be my sister again. I never cared about the others in our cabin. I didn't. They may be my siblings but they're not family. You're my family. I just want my family back. That's all I've ever wanted for you, and for me. Please. That's all I want."

"What about what I want?" Mari whispered.

She didn't think Mason had heard her. But he had.

"What you want is wrong," he said.

Mari stumbled. Wrong... what she wanted was wrong... was that all Mason thought of her? Frankie was his precious little sister, but Mari was just a placeholder? Something wrong? Mari looked down. Her hands were shaking, and had her heartbeat always been that loud in her ears?

Mason seemed to realise what he'd said, too. His face fell, and he let go of her shoulders. "I'm sorry," he muttered. "I shouldn't have said that. I didn't mean it. Frankie, I-"

SLAP

Mari started at her still-shaking hand. It was like it had moved on its own, before she even realised what she was doing. Now Mason had a red hand-print splattered across his left cheek, like a rash. Mari stared between her hand and Mason's cheek, uncomprehending.

"I- I'm sorry, I-"

"You are going to keep walking. We are leaving."

Mason grabbed Mari again, this time by the elbows, and dragged her forwards. His tone was clipped, with no emotion. "Now. So you're going to keep walking. You're leading us out of this maze, because if you don't, I'll find our siblings and kill them off one by one. Then you get to have the death of a sibling on your hands. See how you like it."

For a second there, Mari wondered if she was the one who'd been slapped. "You wouldn't." She shook her head. "You wouldn't kill anyone. Mason, please, tell me you wouldn't kill anyone."

Mason gave her a sad smile. "I can't lie to you, Frankie. Not about that."

Mari was surprised the walls were still standing, because her entire world was crumbling around her.

Mason. Her brother. A killer. How could that make sense in her head? She couldn't mash it together. Even after everything he'd done to her, she couldn't... but she had to, because it was the truth. Mason was a killer. Mari had been so sure he wouldn't ever do anything that bad. She'd trusted him that much even after Mount Tam, yet here he was. Refusing to even bother to deny it. And here she was, feeling like a colossal fool for not seeing it sooner.

"You're a killer," she whispered.

It was almost funny how simple her words were, as they came out: no grand statement, no gasped shock, just a quiet utterance of truth. Because it was the truth, and that was the worst part of all of this.

"That's funny." Mason sneered. "It didn't seem to bother you all that much when you were skipping around after Adela without so much as a care in the world."

"Adela wouldn't kill innocent people on purpose," Mari said. "You... you did. Who did you kill? Was it someone I know? Was it someone Adela knew? Is that why she hates you so much? Is it someone you met after you left camp? Was it a stranger? Mason, please tell me you didn't kill a stranger."

"I did what I had to do, Frankie. Someone had to make the sacrifices for us to get our lives back."

Oh gods. That wasn't a no. To any of them.

"I would never kill someone," Mari said.

"Oh, yes you would. Stop being so naïve," Mason said. "People will do anything when pushed to the right extreme. Why do you think Luke left camp in the first place? You would kill someone if you had to, Frankie. We all would. Now let's go."

"I... I wouldn't..."

Mason scoffed, dragging Mari away by the wrist. As she stumbled along after him, her mind spun like a broken carousel. Mason had killed someone. Maybe multiple someones. Mari's gut swirled at the thought and she felt she was going to throw up again. When had he done... that? How? Why? He was wrong. He had to be wrong. Mari wouldn't ever kill anyone.

They ended up walking for hours.

Mari usually liked walking. She went on morning walks with her siblings sometimes. She especially loved morning walks on hot days. But this walk was miserable. They walked in silence and Mari stubbed her toes twice. The more they walked, the more her instincts went wild, until she felt as if she were having a mild heart attack. The symptoms might be similar, actually. If she managed to get out of this, she'd make sure to ask Will about it. She didn't tell Mason about the instincts. She was only following him so that he wouldn't... kill (Mari shuddered) any of their siblings, but she wasn't going to help him navigate. Plus, maybe the only thing making her feel better about her situation was that he was more miserable than she was.

"Are you going to say anything?" Mason asked her. "Frankie, please."

Mari ignored him. He huffed and went back to walking. Mari was pretty sure that since she was refusing to navigate, Mason was planning on travelling until he either found an exit or something else found them. Mari didn't know which brought her more fear, but judging from the pounding in her chest she was pretty sure that they were going to end up experiencing the latter.

She was wrong on both counts.

Because Mason didn't end up leading her to a hungry monster. And what they eventually stumbled across was a thousand times more terrifying than either of the two options she'd come up with.

"What is this?" Mason asked, staring down at the tunnel into the darkness below.

Mari's breath caught in her throat, and she reached into her pocket, pulling out a crumpled up piece of paper. She held it up in front of the abyss, then took it away again. The drawing was just as much of a dead-ringer as it had been when she'd showed it to Annabeth, Percy, Grover and Tyson. Mason snatched the paper from her, frowning.

"Have you seen this place before?" he asked.

Mari nodded. "It's..."

She couldn't say the words aloud, but they rang though her mind.

It's an entrance to Tartarus.

Mari didn't wait.

Mason was still confused, so he was wary. She elbowed him in the... place that people use to pee standing up, and ran like Hades. Wait, not Hades, Hades was a dick. Hermes. Mari elbowed Mason in his little Mason and then she ran like Hermes. The good news was that Mason was in so much pain that it worked, for, like five steps. The bad news was that Mason eventually got over the pain and he happened to be a much faster runner than Mari.

An arm locked around her neck and she shrieked, thrusting her head back to try and butt his chin, but Mason seemed to have predicted that move, as his hand caught her hair and he pulled. Mari whimpered.

"I'm sorry," Mason said, even though for all his sorry, he was still yanking at her hair follicles. Then, he had the nerve to chuckle. "You used to do that. When you were having a tantrum, I mean. You'd elbow me, then when our Mom was distracted making sure I was okay, you'd run off and try to do whatever you wanted. Then, when you got caught, you tended to headbutt. Luckily," he hissed when Mari stomped on his foot, "you didn't have many tantrums back then."

"Let me go!" Mari snarled. "That's the entrance to the Pit. We have to get out of here - now!"

"Oh, sure." Mason twisted Mari around, still keeping hold of her hair and rolled his eyes. "I totally believe you after you attacked me and tried to run away. There's absolutely no reason for me to think you're just lying to me so that I'm so distracted you have the chance to leave me again."

"I wasn't trying to leave, Mason!" Mari said. "I wouldn't leave you behind here."

"But you'd leave me behind." Mason's voice was flat.

"I-" Mari stammered. "That isn't what I meant."

"No," Mason scoffed. "Of course it isn't. You'll only leave me once you know for sure I'm not going to die."

"What do you want me to do?"

"I want you to stop fighting me, so that we can actually talk!"

"All I've wanted to do this whole time was talk!" Mari roared, headbutting Mason in the face. He howled, letting go of her, and she scrambled around him and away from the Pit. "You're the one who wanted to kidnap me, or - or call me different names, or force me to have nightmares about a little girl I don't even know! Those dreams - they terrify me, Mason! I just wanted my brother to come home!"

"That's what I'm trying to do, Frankie!" Mason lunged for her again, throwing her to the floor and shoving his elbow into the small of her back. "I want to take you home. That's why I went to Luke. It's why I've done all the things I have. Frankie, it doesn't have to end with one of us dying. The gods have already hurt us so much - you died because of them, I lost you, and our Mom because of them. Why should we let them keep doing it? I'm trying to compromise here. I've done my part. I've gotten half-bloods for Luke's army. I'll be hailed as a hero even if I stop now. That's what you want, right? For me to stop. I can give this all up and we can go, leave the rest of it behind and wait for Kronos to win. I'll stop fighting the gods, and you stop fighting me. That's a compromise."

"There is no compromising about the end of the world, Mason!" Mari struggled to get an arm out from under him, blindly slapping the air above her face. Mason grabbed her wrist and squeezed. Gods, she wished she had Drys right now, but her sword didn't go back into her pocket the same way Percy's did. "People are going to die! You lost Frankie, and it was awful, but what about the millions of Frankies that Kronos will be using as Titan food?!"

"Oh, that's right." Mason was above her, but even though Mari couldn't see him, the sneer in his voice was unmistakable. "You get to decide what's right and wrong because you've seen so much now and you know so much better than me!"

"That's not what - Mason, that's not fair!" Mari finally got out from under her brother, by stabbing her elbow into his stomach. He groaned and rolled away. She shot up and back against a wall, fists raised.

"Do you know what's not fair?!" Mason spat, stalking towards her again. "Seeing my little sister die, losing my Mom, finally seeing her again at camp only for her to disappear before I can do a thing about it, thinking she's died again, then when she comes back trying to help her only for her to abandon me for people she barely knows!"

"That's not what's happening!" Mari's heart sped up as she closed her eyes. But that did nothing. Mason was still advancing and Mari was helpless to stop him - he had her sword, nobody knew where she was, he had every upper hand. And he definitely knew it. Mari choked back a sob.

"Oh, really?" Mason stopped in front of her, hands shaking. For a second Mari had to remind herself that he wouldn't strangle her. She was probably the only person he wouldn't hurt. But... that wasn't a good thing. "I'm trying to be a good brother, I even offered to take you home but you won't go! Why won't you go?!"

"Because that isn't my fucking home! That was Frankie's home, not mine!"

"You are Frankie!"

"No, I'm not!" Mari wasn't sure what came over her. It was like when she'd slapped Mason before. Her hands reacted before her mind did, but she felt sick and in that second she just wanted Mason away from her. So she reached forward and pushed.

Suddenly, Mason's face was afraid. Then he disappeared.

It took Mari a second to realise what had happened. Mason was... gone. Because they were standing next to Tartarus. And somehow, Mari had forgotten about that. How the Hades had she managed to forget about Tartarus?! Every demigod's worst nightmare! But she had. And that meant that she had pushed her brother over the edge of the Pit. She'd... this was her fault...

Mason was falling to Tartarus. And Mari felt her heart drop along with him.

"Mason!" She lunged towards the edge, carefully poking her head over. "Mason, Mason, please, I'm sorry..."

A hand lunged for the front of her shirt, and Mari screamed.

Her brother was clutching the edge with his free hand.

"Frankie," Mason begged. "Frankie, help me!"

Mari knew a few things about the Pit from experience. She knew that it was terrifying, but that was a given. She knew that when someone fell into the Pit, they didn't often come out, not unless they moved quickly. It was as if the Pit was breathing or sucking you in. She'd fallen into the Pit last time she was here. She'd moved quickly. But she also hadn't been past the point of no return. Mason was a lot taller than she was. His legs were further down. It was as if there was some kind of level, from which if you fell there, you couldn't return. When Mari had fallen in, she'd brushed right against that level but she hadn't gone past it. She would be in Tartarus if she had. Her instincts had been enough to tell her that. They were telling her again now, and Mason...

Mason was past the point of no return.

LUKE

Luke was starting to have nightmares.

Not the kind Kronos had sent (no, those were dreams, Kronos was trying to help him). Actual nightmares. Terrors about when the end would finally... when he'd make the ultimate sacrifice to prove his loyalty to the Titan Lord.

Loyalty. To the Titan Lord.

Luke shivered. It was all worth it. It had to be worth it. This was the only way to show his father that he, Luke, was more than just a tool for the gods to use, abuse and dispose of as they pleased. To show all the gods that they were all more than tools. Only, things hadn't gone the way he thought they would. If Thalia had just listened to him, just for a minute, then maybe none of this would be happening. She'd been close. He'd seen it in her eyes. She was close to switching sides. To joining him. And having the two of them together might have been enough to bring in Annie, too...

"Master Luke," Kelli the empousa said. "Your army grows impatient."

Right. The army. They had to keep moving, if they wanted to avoid a sudden change in the labyrinth's geography. "Mason isn't back yet?" he asked.

"No." Kelli grinned. Her metallic leg clanked against the floor as she walked towards him. "He was meant to report in last night, was he not? I do hope he hasn't had a change of heart as to where his allegiances lie."

"Mason wouldn't." Luke shook his head. He'd made sure of it. "I'm sure he'll make contact when he can. Besides, we don't have time to worry about him now. It's as you said. The army is waiting for us. We can't waste time, not if we want to find Antaeus before the labyrinth moves again."

Antaeus. The half-crazed, blood-thirsty son of Poseidon. They couldn't make a path around him. Luke hated to admit it, but he almost liked Percy Jackson better. Almost.

"Of course." Kelli linked an arm in his, winking. "Let's go, then."

Kelli was an ally, at best. And ally of Kronos, not Luke. Although, soon enough, there wasn't going to be much difference between the two... Luke suppressed a shudder. He couldn't look weak in front of Kelli, or any of them. Not now. He might be the de facto leader, but most of his associates were still monsters. They'd devour him in a second. They weren't his friends. Mason might be the one real friend he had left. That was why he'd let Mason call Marion Carter by a different name, why he had had lied about what he'd done to Marion. If he ever told the truth, then Mason would hate him. Annie hated him. She'd made that quite clear when he turned up at her door and asked her to run. Thalia probably hated him, and now she was a huntress, anyway. Mason was the one friend he had left. And it was all based on a lie.

Maybe I hate myself a bit, too, he thought.

At least when it was all over, when Kronos... when Luke had done what he had to do, he wouldn't have to worry about things anymore. He wouldn't have to worry about anything. Not even himself. Maybe that meant he didn't have to be scared of going away. Even if it would hurt. And Lord Kronos had been quite clear - it would hurt.

"Are you having second thoughts?" Kelli asked. "Scared?"

"Of course not, Kelli," Luke scoffed. "We are at war. Sacrifices must be made."

"Good." Kelli nodded. Her eyes flamed with a cruel spark. "My my, Master Luke. You are a refreshing half-blood. Most of the others are so... pathetic."

"Oh, I quite agree," Luke lied. "Now, like you said. Let's go."

They walked off, Luke's heart palpitating a little more with every step. Just a little longer, a few more days, and then his part would all be over. He wouldn't have to worry whether he was making the right choice any more. No, no! He was making the right choice. He hadn't turned everyone he cared about against him and betrayed his family for nothing. He was making the right choice. But... why did he feel so terrified? No, it didn't matter. Soon none of it would matter, he needed to be strong for this next part. He couldn't talk to Thalia or Annie... he just wished he could call Mason one last time.

To tell him goodbye.

MARION

"I can't get up, can I?"

Mason's grip on the ledge faltered and he lunged for her, fingers catching on the sleeves of her t-shirt. Mari stumbled but just managed to keep herself from falling over the edge with him.

"I... Mason, I'm sorry." Mari's breath hitched. This was her fault, this was all her fault, if she just hadn't pushed him... "I did this to you."

"No, you didn't." Mason's voice was hollow. "I did this to you. I... I should have believed you. This is Tartarus, isn't it?"

Words had power. That was one of the first thigs any demigod learned, if they survived long enough to get to camp. As if Mason had caught the Primordial's attention, the pressure around the Pit started to get denser. The Pit seemed to be trying to suck Mason in. Maybe it was hungry. Worse, Mason wasn't letting go. "Mason, you're going to take me down with you!" Mari clutched at his hands, shaking. "Please, Mason, don't... I don't want to die!"

Mason's eyes filled with tears. He let go with one hand, and for a second Mari was convinced he was going to let himself fall then and there. The thought had her seizing up in panic, and a part of her almost wanted to grab at him and clutch him to her in desperation. But it would be futile. Mason... was going to fall. Into Tartarus. No demigods had ever gone there and lived to tell the tale. It just didn't happen. Mason was going to... die. He was going to die and it was all her-

"Frankie!"

Mason's free hand pressed something into one of hers. It was cold, and shiny, and Mari realised it was Drys, already in sword-form. "You have to kill me."

"W-what?" Mari's heart dropped.

"I don't want to die in Tartarus, Frankie," Mason whispered. "You have to do this for me. Please, don't make me die like this. If anybody was going to do it I'd want it to be you."

"But-" Mari shrieked as the pressure intensified again, and she stumbled. She dug her fingers into a crack in the rock, but that was barely enough to stop her from falling. She wasn't going to be able to hold on much longer. "I can't," she whispered.

"Damn it, Frankie, kill me!" Mason snarled. "I can't die like this. Stab me, slit my throat, anything would be better than this!"

"I-" Mari screamed again as her fingers slipped from the crack, and the next second she was falling. Falling, falling, falling, down, down, down, Tartarus beckoned and she was helpless to avoid the call. A scream echoed behind her (wait, behind her?) but she didn't have time to focus on that. Mason wrapped his arms around the back of her neck in some kind of hug, and she sobbed, shaking her head. It didn't matter. She was falling. She was going to die.

Something latched onto her ankle and she was still.

Mari's chest heaved. She felt hands on her legs, and two arms tight around them. They were crossed for a tighter hold.

"Marion!" Adela's voice shook. "Are you okay?"

And around Mari's ankles, there was a familiar pair of velvety black gloves. Mari almost dropped Mason in shock. Hands! Adela was touching Mari with her actual hands...

"Frankie," Mason whispered. "Frankie, please. Don't let me die like this, I'm begging you. Kill me."

"Don't you dare make her!" Adela snarled down at Mason. "Don't you dare!" Adela sounded panicked and absolutely sick with horror, but her words barely even registered in Mari's head. Drys was still in her hand. Somehow, she hadn't dropped it. She almost wished she had.

"Mason, please... I can't."

"It's not even that hard, Frankie." Mason gave Mari a watery smile. "I promise. Just slide the dagger across my throat. It's no different than cutting a tough piece of meat. Just close your eyes and pretend you're cutting meat."

I'm vegan, Mari wanted to say, but the words wouldn't come out. "No, no!" Adela started to pull up, but Mason was weighing Mari down and Adela was clearly struggling to hold them both. She didn't have the strength. Mason ignored her and laced his fingers through the hand clutching Mari's knife. He brought her hand up so that the knife was against his neck. "Frankie," he whispered. "Please."

Mari closed her eyes, and lightly dragged the sword across. Nothing happened. "You're not applying enough pressure." Mason's voice was oddly calm. Hysteria danced across the edges of Mari's brain. Shouldn't he be shaking, or at least sound afraid? Shouldn't he be as horrified as she was? He was acting... he was acting like he'd done this before. Mari's head spun at the thought.

"Press harder when you do it."

Mason smiled up at Mari.

"Now try again."

Mari felt like a ghost, disconnected from her body. Her hands shook as she prepared to try and slice her brother's throat open a second time.

"Wait!" Mason gasped.

Hope flurried in Mari's chest. Had he thought of something else? Was he going to find a way out of this, so she didn't have to...

"What did you want to tell me, before you started throwing up dirt?" Mason asked.

Mari burst into tears.

It was the worst possible time to cry, when she was two seconds away from falling into the Pit along with her brother, but she just couldn't help it. Because, deep down, a part of her somehow knew that whatever that dirt had been, it wouldn't happen again. Not now. She'd finally be able to tell Mason what Luke had done to her, all those years ago.

For a second, she thought about lying. But something inside her just couldn't. "Mason..." Mari sobbed. "When... when I was on Circe's island, it wasn't the gods who put me there. Luke did."

Mason's face froze. For a second Mari was afraid the air pressure had done something to him, but then his expression changed. Betrayal. Pure, utter, horrified betrayal. Confusion, fear, pain. Guilt. Mari knew then, no matter what, that Mason had cared about Luke.

"Kill me."

He whispered it up at her, sounding absolutely broken. "Please, Frankie. Kill me."

Without another word, Mari slashed.

This time, she applied enough pressure. Warm, thick, sticky red blood gushed out of Mason's neck. Mari almost laughed through her tears. It looked like fruit juice. Mason looked up at her. He was smiling but the light was leaving his eyes.

"Fran...kie..." he wheezed.

His hand cupped her face.

Then the fingers slackened and he fell.

Into the depths of the Pit.

"NO!" Mari shrieked.

She wanted to jump after him. To stem the bleeding, to do anything to try and save him, but she was already being pulled up over the edge. She screeched into the void of Tartarus as the tiny pinprick figure of Mason's body disappeared from view. The hands kept hauling until she was a good few metres away from the edge and away from her older brother. Then the pressure around her ankles was gone and Adela's concerned face appeared in Mari's vision.

Forgive me, Mason, she thought. I'm so, so sorry.

A fresh wave of sobs wracked her body.

"Let me go!" she screeched. "I need to go back. I need to help him! I can still help him. I can- I can stem the b-bloodflow, I-"

Adela shook her head. Mari's cries tapered off and she looked from Adela to the Pit, and then back. Then, she lunged towards the Pit. If she could just get to Mason, if she could just- just fix him, fix everything, apologise, for everything... then maybe things would be okay. Maybe she could fix it. She could still-

A body slammed into hers.

"Stop!" shouted Adela. "Please, Marion, stop! He's gone. There's nothing you can do! Please!"

Mason had said please, too. Almost the exact same way. Mari's sobs, which hadn't really stopped, overwhelmed her. "I did this!" She howled. "I did it. I did it and I need to help him!"

She rolled over in her position underneath Adela, to stare up at the girl's horrified face.

"Please, Adela, please, I can't..."

She couldn't talk anymore. The words weren't working. Adela's hands were on the ground, either side of Mari's head. Not touching. Mari hiccuped and her sobs dissolved into trembling, broken bawls. She launched herself at Adela, wrapping her arms around the other girl's shoulders and burying her head in Adela's neck. Mari vaguely registered the fluffy movement of Gladys the cat, curled up in the hoodie between them.

Adela didn't hug Mari back but rested her chin on her head, breathing shakily.

"Lo siento, Marion." She whispered. "Lo siento mucho. I never wanted any of this to happen."