In which I decided that maybe I should only write Halloween party one-shots for the rest of my life, because costumes!

Disclaimer for notes: PAIGE IS ALIVE. I know some people were worried about that over at AO3.

(Also please pretend that the Rosewood police are keeping Paige's attack a secret or something and that's why they haven't called anyone to investigate. I just want to have my Halloween Train, gosh darn it, and we can deal with the police next chapter.)

Clarke sighed and pressed End on her phone. Again.

Two hours to go until the Halloween Train left the station, and still no sign of Lexa or Paige. She threw her head back, leaned against the window, and took a deep breath.

"Still no word, hon?" Abby Griffin, in full organizer mode, paused on her rounds to rest a hand on Clarke's shoulder. She'd been checking in with Clarke as each member of the Safety Committee arrived, then setting them about whatever tasks Clarke had on her list. So far she'd put Mrs. Welch on decorations, Ashley Marin was setting up a photo booth with costume pieces, Doris from the cafeteria had joined the catering crew, and now she was looking for a good place for the school nurse to sit.

Clarke shook her head, straightening up from where she was slumped against the wall. "I've called, left messages, texted…I just don't understand. When they left last night, I thought we all agreed to be here by now. Now I don't know how we're going to get everything ready in time. Octavia and Raven are on their way now, but still."

Then it hit her. "Wait, what am I thinking? There's literally only one person in Rosewood who could pull this off!"

Abby smiled and walked on as Clarke picked her phone up excitedly. She bit her lip a little, thinking about Clarke's comment that Octavia and Raven would be there soon. This would be the first time she'd seen Raven in a large group since they started…whatever they'd started, and aside from a fleeting kiss or two, they hadn't been together since that first night (and morning).

And it was driving Abby crazy.

She shook her head and got back to the task at hand.

Clarke was just hanging up when she heard Octavia exclaim, "Are you freaking kidding me?!" She grinned and turned to see Octavia and Raven boarding the train.

Raven's mouth twitched – she was obviously trying not to burst out laughing as she said, "O, I think you should just let it go."

"Hilarious," said Clarke, crossing her arms over her chest and fake-glaring at both of them. She was wearing a shimmery blue dress and matching shoes, and her blonde hair was braided, cascading elegantly over one shoulder. "Emily and I decided to dress as our favorite Disney princesses and surprise each other. So shut up already or I'll…freeze your hearts or something."

She tilted her head a little. "So…what are you two supposed to be, anyway? A midget wrestler and…C-3PO?" Octavia was wearing a black sports bra, black gym shorts, gym shoes, and what looked like fingerless hockey gloves, while Raven had on dusty jeans, kickass work boots, three or four belts around her torso, and some kind of steampunk getup covering her left arm.

Octavia turned to Raven and said, "I literally have no words for her right now." Raven grinned at Clarke. "Imperator Furiosa is here and ready to kick some event-planning ass. But you were pretty much right about the tiny wrestler."

Octavia whacked her on the arm. "Idiots. I'm former UFC champion Ronda Rousey!"

"Yeah, that sounds about right," Clarke said. "You guys both look great."

"So, what can we do?" Raven asked. And Clarke put them to work.

Raven was assigned to decorating duty for now, and she grumbled a little until Clarke shut her up with a look. She grabbed a big box out of Mrs. Welch's trunk and somehow managed to hoist it onto the train. There were rubber spiders and snakes stuffed on top, blocking her view, and as she struggled down the narrow hall she suddenly bumped into someone's shoulder and the whole thing went flying to the ground.

"Shit, I'm so sorry, are you okay?" Raven said, quickly kneeling down to pick up the scattered creatures.

"Language, Ms. Reyes," said a husky voice, and Raven looked up into Abby's laughing eyes.

They both stood and looked at each other, the box between them forgotten. Raven stood up slowly, taking in Abby's glasses, her button-down shirt and tailored jacket and dark jeans. "Let me guess…Sarah Palin?"

"Very funny," said Abby. "Wrong Tina Fey character, but I think you knew that already."

"Yeah, the glasses are a dead giveaway," Raven said, unable to stop herself from reaching up to slide a finger along the side of them. She leaned a tiny bit closer and said under her breath, "You know these glasses drive me crazy, don't you?"

Abby didn't back away, but whispered back, "Why do you think I planned my whole Halloween costume around them?"

Raven's nostrils flared and she took a step back, clenching and unclenching her fists a few times, trying to release some tension. "I'm trying to behave myself here," she muttered.

Just then Octavia came through the door of the car they were in. "Raven, I know you suck at decorating, but I'm pretty sure throwing everything on the floor doesn't count."

Abby laughed at that. "It's my fault, Octavia – I ran into her. Are you two okay to get this stuff picked up while I go check in with Ashley about the photo booth?" They nodded, Raven still a little stunned.

As Abby walked away, she turned and said over her shoulder, "I loved you in Mad Max, by the way."

Raven grit her teeth and tried to ignore the thoughts in her head, the I loved you that was playing on an infinite loop. "Come on, Short Round, help me load this crap back in the box so we can drop it off with Mrs. Welch."

Octavia rolled her eyes, and the two of them got to work.

Clarke was talking with the caterer about where to set up the drink table when she heard someone squeal "OMG it's Elsaaaaa!" She turned to see Hanna running at her, waving her hands excitedly.

"Hanna. What's wrong with you?" Spencer said affectionately, coming in behind her. Hanna said, "Are you kidding me? I love seeing Disney princesses in real life!" Now she was stroking Clarke's braid, and as Hanna walked around Clarke to see her dress from the back, Clarke could finally see the rest of the group.

"I brought reinforcements," said Spencer with a wink.

"Spencer…thank you so much, this is awesome," said Clarke. Besides Hanna, Spencer had brought Bellamy, Aria and, oh my dear sweet Lord, thought Clarke…Emily.

When they decided to dress like their favorite Disney princesses, Clarke was 90% sure Emily would go with Pocahontas. She'd seen a picture in Emily's room, so she knew she already had the outfit.

But holy Agrabah, the sight in front of her took Clarke's breath away. Red harem pants, what was basically a strapless red bikini top, her long dark hair pulled into a high ponytail, gold bracelets high on one arm, gold earrings…

Hanna had completed her circuit of Clarke's Elsa costume and helpfully put a finger under her chin, shutting her mouth. "I know isn't it the best thing ever she's Jasmine when Jafar holds her captive!" she squealed on one breath.

Clarke swallowed. "Yes, she is," she managed to squeak out.

Emily was blushing now at Clarke's obvious appreciation as she walked over and looked Clarke up and down. "Really glad now that I didn't go with Anna," she said. She flipped the end of Clarke's braid. "It's a good look on you."

Spencer cleared her throat. "Um, Clarke? Is there some actual work you wanted us to do, or…"

Clarke snapped out of it. "Yes! Okay." She took Emily's hand as she handed out assignments. "Hanna, Aria, you two are going to relieve Raven on decorating duty. She just wrestled a box of decorations farther back on the train, so you can go check in with her." She paused. "Wait – what are you two supposed to be? And why are you here? I thought you weren't coming."

"Duh, I'm 80s blonde bombshell Cheryl Ladd," Hanna said with a flip of her feathered hair. She was wearing high-waisted red satin pants with matching red heels, and a red satin track jacket unzipped far enough that it was obvious she wasn't wearing a shirt under it.

"I tried to tell her that jacket-only look probably violated our school dress code about 10 ways, but she just pointed at Emily and I had to concede," said Spencer. "Care to guess who Aria is?"

"Um…Whistler's Mother?" said Clarke. Spencer, Emily, and Bellamy burst out laughing, Hanna looked confused, and Aria sighed. "I'll have you know I'm noted suffragette Elizabeth Cady Stanton," she said.

Hanna chimed in, "So what happened was, Aria wasn't going to come this year, because of what happened last year, and being an amazing friend I was going to hang out with her at her house. But then we got the call for help from Spencer, Aria grew a backbone, and we each just threw a costume together from what we already had."

Bellamy said, "The hardest part for them was probably choosing which satin track suit and which suffragette costume to pick out of their closets." He and Spencer were dressed straight out of the Roman Empire – Bellamy wore a crown of laurels, a tunic, and a cloak fastened over one shoulder, while Spencer had a sheer flowing white gown with a slim belt, a sparkly headband, and a bow and arrow slung over her back.

"Well, at least we didn't go totally cliché and dress as Katniss and Peeta," said Hanna.

"Hanna. How many times do I have to tell you, I'm not Katniss?" Spencer said.

"Geena Davis then, whatever," said Hanna.

"I'm Diana, Roman goddess of the hunt, and my mortal love here is Emperor Augustus." Spencer twined her arm through Bellamy's as she spoke, and they smiled at each other.

"I always pictured you as more of an Athena," Aria said.

"Well, I would have had to be Minerva, Athena's Roman equivalent," said Spencer. "But I really wanted the cool accessory."

"Nerds! We need to get to work here!" Hanna interrupted. Clarke finished giving out their assignments and asked Spencer to stay back. The rest of them dispersed.

Clarke looked at Spencer. "I'm worried, Spencer. There's still a lot to do, but also I'm just worried about Paige and Lexa. No one's heard from them all day, and it's not like them to just not show up."

Spencer thought for a moment. "Yeah, it's not like them at all, is it?" She put a hand on Clarke's arm reassuringly. "Hey – why don't we finish up here, and then maybe Aria can call Ezra and have him go check on them or something?" Clarke nodded, but her eyebrows were still creased.

Spencer pulled out a clipboard. "All right, Griffin – let's get to work. Moments like these are why I live by the motto 'When you feel out of control, make a list.'"

Clarke took a closer look at the clipboard. "Did you make your own checklist?" she asked.

"No, this is the standard template I use for any event longer than one hour that involves more than four people," Spencer said. "Come on, this isn't amateur hour. Tell me what still needs to get done and we'll make it happen." She paused, then added with a mischievous grin, "Unless you'd rather…build a snowman?"

"God, not you too," groaned Clarke. And the two of them got to work.

Together, the members of the Safety Committee and Clarke's extended friend group were able to get everything ready just in time for the doors to open on the Halloween Train.

The first person aboard was Marcus Kane, a former colleague of Abby's who now worked at another high school. He was ostensibly the Halloween Train's organizer, but once Abby called him and volunteered the help of the Safety Committee, he quickly bowed out of doing the work and left it to them.

He strode aboard confidently, a black cloak billowing behind him. Abby and Clarke were near the main door to greet people as they boarded, and Kane went straight to Abby, ignoring Clarke.

"Abby, the train looks wonderful," he said, not looking around. "Many thanks to you and the Safety Committee for your help."

Help? thought Clarke. We did everything! She didn't like the way he clasped Abby's hand between both of his, or the way he looked at her, or his patronizing attitude, or his generic vampire costume.

She happened to glance over at the "bar" that they'd set up for serving Halloween-themed, non-alcoholic drinks – Raven's domain for the evening – and she noticed that Raven was clenching her jaw as she watched the scene.

Abby was saying, "The Safety Committee was happy to do the work. We're hoping this is another chance to bring people together."

Kane leaned in and said, "Well, I'm certainly happy that it's brought us together for the evening."

CRASH! All three of them turned to the bar, startled. Raven had dropped the glass she'd been wiping for the past several minutes.

"Whoops!" she said with a forced smile. "First party foul of the night."

"I'll help you clean up," Abby said, hurrying over.

She bent down to help Raven sweep the shards onto a towel. "Are you okay? Did you cut yourself?" Abby said.

"I'm fine," Raven said curtly. She jerked her head toward Kane. "I don't like that guy."

Abby grinned at her and whispered, "Aww…jealous, baby?" Then she actually winked at Raven, stood up and went to dispose of the towel, leaving Raven gaping after her.

The students were flooding in now, in ones and twos and threes. Clarke spotted several familiar faces, and lots of people she hadn't met yet.

She saw Mona Vanderwaal in a flawless Maleficent costume, horns and black cloak and staff and everything.

She saw Hanna's friend Lucas, looking Comic-Con ready in a homemade (but authentic) Kylo Ren costume.

She saw Alison DiLaurentis dressed as…well, Clark wasn't sure what she was dressed as, but she was looking dangerous in a floor-length hooded black cloak with a skintight, sleeveless black-and-white striped dress and long black gloves.

Then suddenly, Noel Kahn was in front of her. "Hey – it's Clarke, right?" he said. Clarke nodded and said, "And you are…James Dean?" He was wearing jeans, a white t-shirt, and a black leather jacket.

Noel put a hand to his heart, mock offended. "Please. I'm Nick Jonas!" As he wandered off into the crowd, he called back, "Remember – conceal, don't feel!"

The rest of the gang joined her near the door. It was almost time for the Halloween Train to depart.

Hanna pulled Spencer, Aria, and Emily to a relatively uncrowded corner. "What's up, Han?" Spencer said, a little worried. But Hanna wrapped them all in an impulsive group hug and said, "It's been so long since it was just the four of us. I love you guys."

And the four Liars hugged there as the whistle blew.

They broke apart as one more person jumped up the stairs and onto the train.

It was Lincoln, wearing red gym shorts, fingerless boxing gloves and not much else besides a black cloak.

"Daaaaamn," Emily whispered, taking in his abs and general lack of clothing. Spencer and Aria both looked at her, amused, and when she realized she'd spoken out loud she just shrugged and said, "What? I have eyes."

But Hanna missed that whole exchange, because she was looking back and forth between Lincoln and Octavia with a terrifying intensity. Spencer noticed and put a hand on her arm, saying "Han–" but Hanna shook her off and stalked over to him as the train started moving.

Lincoln looked surprised and happy to see her. "Hey! I thought you were staying home with Aria tonight," he said.

"Well, I'm not," said Hanna. "Which means I got to see your little couples costume firsthand."

"Couples costume? What are you talking about?" said Lincoln, genuinely confused. Hanna pointed angrily at Octavia, who quickly looked away and pretended that she hadn't been watching the whole exchange.

Lincoln actually laughed out loud. "Is she Ronda Rousey? That's awesome," he said.

"Is it? Is it awesome?" said Hanna. "You're obviously one of those…fighter…people too. So what, did you guys plan this?"

"Look, I wasn't even going to come tonight," said Lincoln. "But Lexa asked me to come in case she needed help, and Octavia had mentioned it at the gym one day too, and I thought you were staying with Aria so that's why I didn't say anything."

"Just – just stay away from me," Hanna said, and she stormed off to another train car.

Bellamy came over. "Hey, man," he said as they bro-hugged.

"What just happened?" Lincoln muttered.

Bellamy clapped him on the back and said, "Hanna just happened. Give her some space, I'm sure she'll be fine." He looked at Lincoln. "Randy Couture?"

Lincoln nodded. "Where's Lexa?"

"You haven't heard from her?" Clarke said as she hurried over to them. "I've been trying to call her all day. Can't get ahold of her or Paige."

"I thought she was here," said Lincoln. He frowned. "That's not like her."

"Come on, let's go get Aria to call Ezra and have him check on her," said Clarke, pulling Lincoln over to where Aria stood.

Bellamy walked over to Octavia, who was near the bar with Raven. "So…is there a story here? You and Lincoln and your matching fists of fury costumes?"

Octavia glared at him. "How was I supposed to know what he'd dress up as? There's no story, so just butt out." She stalked off in the opposite direction from where Hanna had gone. Bellamy shook his head.

"Buy you a drink, stranger?" Spencer slipped her arms around his waist and he pulled her close.

"Ow," said Bellamy.

"Oh, sorry! That's my clipboard," said Spencer. She put it on the edge of the bar. "Is that better?"

"Where were you even keeping that?" Bellamy said.

"A goddess never tells," she said. "Your mortal brain couldn't handle it."

"Don't insult my mortal brain, Princess – you owe me one for roping me into helping with this, and it's middle-aged-woman central. Mrs. Welch asked me about every book I've ever read, and I think Ashley Marin touched my ass on purpose."

Spencer threw her head back and laughed at that. (God, he loved her laugh.) "She gets a little handsy after a couple glasses of wine…and–" (she lowered her voice) "she's always had at least a couple glasses of wine."

"Well, you can make it up to me later," Bellamy said.

Spencer pretended to consider it. "I don't know…my checklist isn't going to check itself…"

Bellamy leaned in close and said in a low whisper that sent shivers down Spencer's spine, "Well, you are the goddess of the hunt. So prove it and come find me." Then he winked and sauntered off, for once leaving Spencer Hastings speechless.

After she wandered off, Octavia found herself in a mostly deserted car. She was looking out the window, watching the stars come out, when she saw the main guy from V for Vendetta sneaking up behind her.

When he put a hand on her shoulder, she reflexively dug an elbow into his gut and stomped on his foot.

"Ow!" he said, doubling over.

"Caleb?!" said Octavia. She helped him sit down at a table. "What are you doing here? I thought you got stuck in Ravenswood!"

He took a deep breath and flipped his mask up, looking at her with a rueful smile. "I wanted to surprise you. Apparently, it worked a little too well." Then, half to himself, he muttered, "I have GOT to stop sneaking up on people on these trains."

She sat down across from him. "Man, it's good to see you. I'm worried about Paige and Lexa – they didn't show up tonight, and no one has seen them. And everyone is giving me shit because Lincoln and I have matching costumes."

"Lincoln is dressed as Ronda Rousey, too?" Caleb said, grinning. "I've gotta see this – Lincoln in a sports bra is on my bucket list."

She smacked his arm across the table. "Careful, tiny angerball," he said. "That's one of my few uninjured body parts." Then he looked at her more seriously. "Why is it a problem that you and Lincoln have matching costumes?"

Octavia put her head on the table and groaned. "I don't know! I guess it looked like a couples costume or something, but Hanna flipped out about it and even Bellamy didn't seem to get why it's not a big deal."

"Hey," said Caleb. She looked up at him. "It sounds like just a misunderstanding. And besides – it's a little-known fact that Ronda Rousey was the original love interest in V for Vendetta, so really we're the ones with the couples costume!"

"You're stupid," said Octavia, smiling. She took his hand. "Thanks for showing up tonight."

"Anytime," Caleb said. "So should we go party or what?"

They stood up and Octavia impulsively threw her arms around him. Caleb hissed in pain. "Please tell me that was the manliest hiss of pain you ever heard," he said. And they walked off to rejoin the others.

Raven was back in the main car, serving up Vampire-tinis and Hemorrhaging Marys and other awful Halloween-themed non-alcoholic drinks. It was actually all right, but it wasn't what she wanted to be doing, so she mixed up a bunch of drinks, left them on the bar, and grabbed a tray to join the caterers who were circulating throughout the train.

She spotted her target right away. Abby was standing apart from the crowd, looking around and making sure everyone was safe. Raven brushed behind her, much closer than was necessary, and whispered, "I found somewhere we can be alone."

Then she was off before Abby could even turn her head. Raven walked up to a group of witches and offered them some horrors d'oeuvres, looking back at Abby over her shoulder with a smirk.

Serving appetizers gave her the perfect opportunity to tease Abby, and as Raven weaved in and out of the crowd, she whispered one sentence at a time just to see Abby flush.

"There's a car at the back with private cabins."

And, a few minutes later: "They're locked, but I'm pretty sure I can pick the lock."

Even later: "So the good news is…they lock."

And, brushing by her one last time: "I'll meet you there in 10 minutes."

Like her mom, Clarke was keeping an eye on the proceedings, walking through the various cars to see how everything was going. She was still worried about Lexa and Paige, but luckily she had Spencer to distract her with her impressive efficiency, and of course Emily to distract her with sweetness (and, um, cleavage). Emily was on her arm as she made the rounds, and they turned heads every time the two of them entered a train car.

"Do you think we should invite Mona to walk around with us?" said Clarke, spotting her in her Maleficent getup. "Make it a Disney trio?" Emily shot her a look. "After the stunt she pulled last year? Organizing her minions, getting Melissa to drug Aria? I'm amazed they even let her on the train."

She noticed that Clarke still had a slight frown. "Hey," she said, putting a hand on Clarke's arm. They stopped walking for a minute in the passage between two cars, facing each other. "I'm worried about them too," said Emily. "Have you talked to Aria? Did Ezra manage to track them down?"

Clarke shook her head. "There wasn't anyone at Paige's house, and I've actually never been to Lexa's house so I'm not sure where to look for her."

Emily pulled her into a hug. "As soon as we're off this train, let's try to find them," she said.

Clarke nuzzled into her bare neck. "You're so sweet. Is it wrong that all I want to do is chain you up in my dungeon?" she growled.

Just then, someone entered the passage with them. "Now there's a Disney movie I could get into," Alison said.

Emily broke away from Clarke. "Oh. Hi."

"I didn't mean to interrupt, just passing through," said Alison, brushing between them, closer than necessary.

When she was in the next car, Emily looked at Clarke. "What is she even supposed to be?"

"I was thinking sexy Hamburglar," Clarke said with a grin.

"Okay, a – don't call Alison sexy. That girl is trouble, and I would know better than anyone," Emily said. "And b – can we stop babysitting everyone and find somewhere to make out already?"

Clarke took her by the hips and pulled her close. "I thought you'd never ask." She grabbed Emily's hand and pulled her toward the next car. "Let's get out of here, it's freezing."

Emily said with a grin, "I thought the cold never bothered you anyway." Clarke shot her a look, and they hurried on.

"Where is everyone?" Octavia said to Caleb. They were in the main car, with none of their friends in sight.

He shrugged. "Don't know. Do you want to dance or something?"

"Sure," she said. "Want something to drink?"

"Aw, you're such a gent," Caleb said. He dodged the light punch that followed.

Octavia walked up to the drink table right as Lincoln wandered over. "Rousey, huh?" he said.

She nodded. "Couture?"

"Yep."

"Nice."

Octavia grabbed two drinks and went to join Caleb where he was dancing in a small crowd of people.

And she tried, so hard, not to look back.

Aria and Hanna were sitting at a table in the dining car. Hanna was drumming her fingers on the table, still looking peeved. "Han, it was just a coincidence," Aria said. "Come on, get over it and let's have some fun."

"How about you let me pout, and I'll let you fight for the right to bear arms?" Hanna said.

Aria sighed. "It was the right to vote." She looked at Hanna. "But I feel like you knew that."

Hanna shrugged. "Whatever. We all have our role to play."

Aria looked over her shoulder as someone entered the car. "Well, right now I'd suggest that you play the role of 'girl who realizes she overreacted.'" Hanna turned and saw Lincoln holding three drinks, looking sheepish.

He walked over hesitantly and put all three drinks down on their table. "Um. I didn't know what you liked."

Hanna sniffed at the drinks. "How about a shot of honesty?"

"That was terrible," Lincoln said. And Hanna cracked a little smile. "Come on," she said with a sigh. "Let's go somewhere and talk."

Aria watched them go. She thought about texting Ezra, but Spencer had been hounding her about getting him to track down Paige and Lexa, and she didn't want to bother him again.

She looked out the window. Just then, they came out of a tunnel, and the moonlight shone on the window so that she could see something written in the condensation:

Do you know where your drink has been, Aria?

And her heart froze in her chest.

Clarke and Emily tried every cabin in the sleeping car until they found one that was unlocked. They heard noises coming from one of the cabins and exchanged an amused look. Apparently they weren't the only ones who had thought of this.

As soon as they were inside, Emily locked the door and turned to face Clarke, her back against the door. "So, Elsa…"

Clarke crossed the room and kissed her before she could say another word. In between kisses, she muttered, "I swear to God, if you were about to make a Frozen joke…"

"I…forget what I was going to say," breathed Emily, as Clarke tugged out her ponytail, her lips on Emily's neck.

Eventually, they found their way to the couch and stretched out on it, still kissing. Suddenly, Clarke sat up. "Do you smell that?"

Emily sniffed. "Smells like…smoke." They looked at each other, wide-eyed. Then Clarke jumped up and went over to the door, testing the doorknob to see if it was hot. She opened it tentatively and reached back for Emily's hand.

The corridor was filling with smoke. "Stay low," Clarke said.

A nearby door opened and two people tumbled out. "Raven?" said Clarke.

Then she saw the woman Raven was shielding behind her, trying to button up her shirt and adjust her glasses at the same time.

"MOM?!"

Next time: Oh, who cares, they won't be in Halloween costumes so whatever. (Just kidding, we'll check in with Paige and Lexa and find out more about the fire on the train!)