Najia brought them through the service section of the hotel to reach the actual section of land the hotel had been built over. "We've just passed the entrance to the back of the spa," she said, holding out a map of the hotel. "We should be here now."

"You're not going down there," Robertson said. "It's too dangerous."

"I eat danger for breakfast," the Doctor said, narrowing her eyes before falling into a grin. "I don't, I prefer cereal. Or croissants. Or those little fried Portuguese..." she waved a hand. "Never mind, it's not important."

They reached the door, though Robertson hurried forward, gesturing fervently at the signs. "Ha! See? Look at this. Keep out. Danger of death. You are not authorized to go in here."

The Doctor held up her sonic. "Dude, I've all the authorization I ever need." She soniced the door's keypad until it sparked. "I call people dude now."

Jade rushed up behind them. "Doctor, I need to speak to you."

The Doctor pulled open the door. "We need to do it as we walk. There's something behind this door people want to keep locked away." She hurried into the darkness, the Singer a step behind. As Yasmin entered, they all began to move along the walls, attempting to find a light switch.

"Oh, sure," Robertson scoffed, "it's a party. Everybody can come."

"Thanks." Jade followed the Time Lords. "Doctor, I've seen these spiders before."

The lights flicked on, Yasmin turning from the controls that she'd found. "Nice work, Yaz," the Doctor grinned at her, leading the way down the tunnels.

"No, not nice work. None of you are allowed down here," Robertson pointed around at all of them, though he still followed.

"Are all of your terrible hotels built on repurposed sites?" the Singer asked him.

He shrugged. "Well, that's the business. I mean, every city in the world, big or small, has an area that they want repurposed. Maybe it's not too pretty, maybe it's never been used, maybe it's an industry that's died. We go in and we help them figure it out. We get a good deal, but we give them world-class facilities. It's a win for everybody."

"A network of mining tunnels could explain how the bigger spiders are moving," the Doctor turned to face him. "The question is, does that make your hotel their target or their base?"

They quickly determined, through the discovery of both the spiders' food storage cavern and the mass of toxic waste fermenting under the hotel, that the spiders had come from an accidentally still alive specimen from Jade's lab, feeding on that waste.

The group had just returned from their exploration under the hotel when the four left behind rushed back into the kitchen, Graham and Ryan looking far more terrified than the gleeful expression on the twins' faces. The Singer was impossibly relieved to see that they were still alive, and enjoying themselves.

"We've found out what's going on..." Yasmin started.

"Massive spider," Rikou started, interrupting her.

"In the ballroom!" Nella finished.

The Doctor lifted her eyebrows. "How massive?"

"The size of a large van," Graham said, breathing hard.

"Wow, that is massive."

Jade nodded. "It must be the mother and the rest are the babies. Some stayed here, some went out into the city, their pheromones disrupting the spider eco-system, causing other spiders to behave abnormally."

"Of course. Najia, you were never the link." The Doctor turned to Jade. "Your colleague, Anna. What if she had the same pheromones on her, accidentally calling out to a spider that had gone out hunting from this hotel? All these spiders answering the same call, because in the end, every living thing as the same instinct. To come back home." The Doctor couldn't seem to stop herself from glancing at the Singer.

"That's very touching," Robertson said. "But there's a plague in my hotel and it needs to be fixed."

The Doctor faced him fully. "Show me your panic room."

-X-

Locked by a thumbprint and retina scanner, Robertson's vault was incredibly well-stocked, based on the number of boxes. "It looks like a bank vault," Graham said.

"My lockdown palace. I have one in every hotel, just in case it's needed. Not finished yet, but still."

"What's in the boxes?" Ryan asked.

"Food, water, entertainment system, a book. I could survive in here for six months if I needed to. And I've got a huge stash of weapons, enough for all of us. Enough for two guns apiece."

"Oh, mate, she's not going to like that," Ryan said, glancing between Robertson, the twins, and the Doctor.

"No, I'm not." The Doctor shook her head. "You are not shooting those creatures."

"Told you."

"They're mutants," Robertson argued.

"Caused by you," Jade pointed out.

"Your carcasses, lady, not mine."

The Doctor stepped between them. "Whatever happens, there are living, breathing organisms out there and we treat them with dignity." She looked to the twins, who still had their weapons out.

"They're on stun," Rikou said.

The Doctor ground her teeth. "So here's what we're going to do."

"Shoot them!" Robertson interrupted.

"You're not going to shoot them," Nella said, looking very tempted to shoot him herself.

Robertson flung up his arms. "What's wrong with you people? What is wrong with this country? Why don't you do what normal people do? Get a gun, shoot things, like a civilized person."

The Doctor held up a hand. "Because I've got a much better idea. Spiders are roaming this hotel searching for food. We're going to lure them in here with the promise of food, then deal with the spider mother in the ballroom." She blinked. "Oh, that sounds like what the best novel Edith Wharton never wrote."

"Once they're in here, what happens?" Najia asked.

"We shut them in and isolate them."

Robertson frowned. "You're going to let spiders use my panic room?"

Jade nodded. "They deserve a humane, natural death."

"Shooting's quicker."

"Would definitely shut you up quicker," Nella mumbled, very obviously fingering her weapon.

"How are you going to lure them?" Rikou asked the Doctor, as though his twin sister hadn't spoken.

"Spiders gravitate to their food through vibration. Any ideas?"

Ryan grinned. "Easy. Raze. Am I right?" he focused on Yasmin.

She only shook her head. "I don't know what you're saying."

He groaned. "Yaz, you're so uncool right now."

-X-

The Singer was quickly reminded how little she actually liked Earth music when Ryan began to blast his music from the panic room. The twins seemed to quite enjoy it and, if they weren't facing down mutated spiders, she was fairly certain they would have started dancing.

The Doctor got suited up with a collection of essential oils from the spa in order to control the spiders. The group reconnected at the ballroom after the smaller spiders were successfully lured to the panic room.

With a nod to the Doctor, the twins opened the doors to the largest spider. It really was quite large, shuffling on the opposite side of the ballroom. "Ooo! Very big spider," the Doctor said appreciatingly.

"What have we got?" Ryan glanced at her backpack.

"Peppermint and tea tree oil diluted with water. Spider repellent. I'm hoping this'll help us herd it out."

"You want us to herd out a giant spider? They're attacking people."

Jade moved forward, frowning at the spider. "Stop a second. Can you see that?"

It became clearer that the spider was attempting to climb the wall, but couldn't manage it. She kept sliding as she scrambled.

"It's grown too big."

"She's suffocating," Jade nodded. "She's got too big to breathe efficiently. Even moving around in here, it's using up what little oxygen she can absorb. She won't survive for long. She's more scared of us than we are of her."

The Doctor approached the spider carefully. "I'm so sorry this has happened to you."

"So what do we do, just leave her?" Graham asked.

The doors to the room burst open, making them all turn to see Robertson, human gun in hand. He did not get far before Nella had shot him, freezing him in place.

"Charity!" the Doctor cried.

"He'll be fine," Nella waved her hand at the stunned human. "Though, Doctor, we can't just let the spider linger in death." She glanced at Rikou, making the Singer turn to do the same.

Her son had taken off his sunglasses, pressing a hand to his eyes. He wasn't shaking and she could not tell if he was crying, but there was something wrong. "She's suffering," he said, his voice rough.

The Singer moved closer to Rikou and put a hand on his shoulder. Without asking, he turned into her, letting her hold him tightly, rubbing her son's back. She looked up at Nella. "Please."

Her daughter did not wait for confirmation from the Doctor. She turned to the large spider, whispered something, and shot it. The spider fell back from its attempts to climb, going stiff immediately. Rikou stilled, though he didn't move back from hugging the Singer. If anything, he held her tighter.

She'd known this entire time that her son was empathetic, but she had been careful, when he'd been a child, to keep him away from quite a lot of pain. She hadn't known exactly how his abilities worked, but she could make guesses. And it appeared the sunglasses helped him restrict it, or he had, like Nella, gotten very good at turning it off.

But it was still there. Underneath the surface of every interaction was likely desperation to follow his natural instinct and fall into the emotions of other people. The Singer could only imagine how hard it was to suppress.

How much her twins had to go through every second of the day in order to appear even as slightly well-adjusted as they did.

The Singer did have to thank the Master for that. Her spouse may have used their control for manipulation, but they knew far more about that sort of thing than the Singer ever had. She'd solved every problem by hiding and drawing into herself. The Master had at least given the twins another option and, thankfully, it seemed to have worked.

At least, as much as it ever could.

-X-

Before returning to the Doctor's TARDIS, the Singer made the executive decision that the twins needed a break. Thankfully, Yasmin's sister was still home when they arrived and took the step herself to show the twins something in her room.

That left the Singer with the humans, who all decided to actually have that cup of tea with Yasmin before their official promised goodbyes with the Doctor, who had returned to her TARDIS. She had wanted to go back with the Doctor but didn't want to be too far away from her twins, just in case they needed her for anything.

The humans and the Singer sat around Yasmin's table for a few minutes in silence before Graham finally spoke. "You're called the Singer, then?"

"Yes."

"And the Doctor's sister."

"Little sister, yes."

"With teenagers."

The Singer raised her eyebrows. "Are you just going to continue listing off facts about my life to me? Or shall I just tell you a general summary of my and the Doctor's life?" She looked around at the not-quite-companions. "My name is the Singer. I am the little sister of the Doctor. We traveled together in the past for a brief period but separated for mutually understood reasons. My twins were raised by their other parent for the majority of their lives. I was believed dead for a period of time, which was part of the reasons the twins were with my spouse."

Graham leaned forward, his hands cupped around his tea. "Who...who was your spouse?"

"Someone you should never desire to meet." She sipped her tea. "They are dead."

"I'm sorry."

The Singer almost smiled. "It happens often. My spouse has a tendency to appear dead and then reappear perfectly healthy."

"Because of that regeneration thing?" Ryan nodded.

"Partly. And because they have a persistent dedication to staying alive, even when I and many others would much prefer they didn't." She sighed. "It is complicated. Just as my relationship with the Doctor is complicated."

"Family always is," Graham said, glancing at Ryan, though the boy entirely pretended to ignore him.

-X-

While the humans were successfully left with their families, at least until the promised actual goodbyes with the Doctor, the Time Lord family stood around the Doctor's console.

"What do you want to do?" the Doctor asked, focusing on the Singer. "We can..."

"I think it would be best," she cut in, "if we did not travel together. It has never worked." Technically, they'd had quite a long stretch together right after a regeneration, when they'd both been mourning and desperate for anything to distract themselves. But the Singer knew she'd been using it to avoid her own problems, too busy focusing on how to save the universe to ever dream about helping herself.

The Singer did still want to adventure. There was some itch in the back of her mind now, some tug towards seeing more of the universe, but she didn't know how long she and the Doctor would be able to last together.

They hadn't exactly parted on good terms the last time, after all.

The Singer had walked away arm in arm with Missy, and before that, they'd fought over how she was dealing with having Missy and the Master together, and before that, centuries of fighting and parting and being forced together again.

Now, if the Singer had to name what she was annoyed with her sister about, it was the fact that the Doctor was clearly blaming the twins for the fact they'd been raised by the Master, even though it was the Doctor's fault that they'd ever been put in that position. The Doctor had not directly said it, but the Singer could read her sibling's expressions by now, even this new regeneration.

The Doctor ground her teeth. "Fine. Right. Good." She paused. "Where are you going to go?"

"We have a TARDIS," Rikou said. He'd put on his sunglasses again, returning to the refined character the rest of the universe was used to, but the Singer was very thankful he let drop around her, even if only slightly.

"Right then." The Doctor rolled her shoulders. "Is this goodbye?"

"We have a mental bond," the Singer reminded her. "And don't think I'm going to let you go too long without letting me repair your TARDIS." In unison, she and the twins moved towards the TARDIS doors, though the Singer paused before leaving. "Keep those companions if you can, Doctor. You have much less fun traveling around the universe when you don't have anyone to show off to."

When the Singer closed the doors and looked to the twins, they were smiling at her, and the Singer felt slightly less bad at abandoning her sister.

She had the twins back. She wouldn't lose them again.

A/N: I mean, did you every honestly expect these two to willingly want to spend that much time together? Too many unresolved complications between just the two of them, let alone what the twins add to it.

We got to see the Singer having a mini explanation with the companions. Definitely not as much as she's shared with previous companions, but both the Singer and the Doctor aren't really into sharing this time around.

And also some of the real negative side-effects of the twins' abilities! Not a fun thing for either of them, sadly.