Happy Halloween everyone!

DISCLAIMER: I don't own Legends of Tomorrow, Arrow, or the Flash. I also don't own Back to the Future, Indiana Jones, Harry Potter, The Matrix, Sherlock Holmes, or Nosferatu.

WORD COUNT: 2598

Nate and Amaya groaned as Sara set them down in 2016 Central City. The two newer members of the team were still quite unused to time-travel. Mick stood up right away, and the rest didn't need much time to shake off the side-effects. "What're we doing here?" their resident pyromaniac asked.

"Before we left 2016 last time, Cisco Ramon invited us all to the S.T.A.R. Labs Halloween party," Stein explained, "So I asked Sara to bring us here and now. 'Now' being Halloween 2016."

"You're stopping in the middle of the mission for a party?" Amaya asked disbelievingly, "I thought we were going to look for Rex's killer and your captain!"

"We are," Sara assured her, "But with the exception of you and Nate, we've been at this almost non-stop for six months. So yes, we're taking a day of much-needed shore leave, and you're welcome to join us."

After a bit more protesting, Amaya reluctantly allowed herself to be dragged off by Sara to the fabrication room to get her a costume. Nate followed, while the rest of the men retreated to their rooms, already possessing everything they needed for their costumes.

Jax came out first, dressed in the same suit he'd worn on his date with Betty Seaver in the fifties. He claimed he was going as Marty McFly from 'Back to the Future', even though it bore no resemblance to the suit Marty wore to the 'Enchantment Under the Sea' Dance.

Mick was next. He'd originally planned on not going to the party at all, but now he had a real ninja outfit and an opportunity to wear it. Plus he wanted to freak out the goody-goodies on Team Flash. The shuriken Amaya had found for him was tucked in one of its many hidden pockets.

Stein had chosen the French Musketeer clothing he'd worn while the team was saving the King of France. He'd initially considered, back when they were in the middle of that mission and Rip had still been with them, trying to convince the captain and Mick into going as the Three Musketeers, but now Rip was missing, and Mick had made his feelings about that disguise very clear.

Ray was still absent when Nate and the two women joined them on the bridge. Sara had pulled out the cowgirl outfit she'd worn in the Old West. When asked if her pistol was real or a prop, she'd smirked and otherwise ignored the question. Amaya was in a black, form-fitting, fake-fur catsuit, with a headband with cat's ears and whiskers painted on her face. Being from the forties, she was a little uncomfortable with it, but had agreed to give twenty-first century costumes a try. And as for Nate, he'd gotten himself a broad-brimmed hat, a leather jacket, and a whip – he was going as Indiana Jones, although he said that he'd also considered the Terminator. Both references were completely lost on Amaya.

They waited nearly half an hour and were considering sending a search party when a clanking sound finally announced Ray's presence. The (former) Atom had saved his steel plate armour from his brief stint as a knight in the medieval period, but he was positive that he had some of the pieces on wrong, even with Gideon talking him through the process.

Once everyone was finally gathered, they exited the Waverider, making a beeline for S.T.A.R. Labs. Stein was on his cell phone, calling his wife to let her know he was back, however briefly, and that he would be home to help her with the Trick-or-Treaters later that night (this being the first Halloween since 2013 in which he'd had a chance to).

Five people exited the train from Star City and immediately ducked into the restrooms to change. Team Arrow had also gotten an invite to Team Flash's party, but not everyone could make it. Oliver had gotten the idea for City Hall to host a children's Halloween event – so that all the kids in the city could have somewhere safe to go Trick-or-Treating – and of course had to be there himself, Curtis had promised his husband that he'd attend another party with him, Felicity had plans with her boyfriend, and John couldn't take the risk of being out in public so soon after his escape. So Oliver had given Thea the day off work and charged her with the 'task' of bringing his new recruits to Central City to properly introduce them to Team Flash and the Legends. Quentin also took the day off and came along, wanting to spend some time with his only remaining daughter.

The three men emerged from the restrooms first. They weren't the only ones at the station in costume, so they didn't attract much attention. Quentin and Rene had gone with the classics – Dracula and the Wolfman, respectively. Rene had originally claimed Dracula, but had eventually been convinced that the Wolfman would better fit his codename of 'Wild Dog' (and yes, he had used the argument as another failed attempt to change said codename).

All attending members of Team Arrow had chosen some sort of reference to their alter-egos. Rory was wrapped up in bandages as a mummy, saying they were just another kind of rags. He'd also considered going as Harry Potter, given his status as the only member of Team Arrow in its history to consistently use magic in combat (Oliver didn't count, as he'd only learned how to channel Light Magic to counter Damien Darhk's power, and hadn't really bothered to use it since).

Eventually, both girls joined them, and Quentin found himself being transported back to the days of dealing with his daughters' teenage years, and the less-than-sensible fashion choices that came with them. Thea wore a short, red dress that stopped at her mid-thigh, flaring out at the bottom thanks to the poufy white fabric underneath, with a neckline that left little to the imagination. All that covered her was a little red hooded cape. She made a very sexy Little Red Riding Hood.

Evelyn's choice carried a little bit of irony. She wore an almost equally short sleeveless white tunic, had her hair in a braid, and carried a fake bow with a quiver of toy arrows slung over her shoulder. She was dressed as her namesake Artemis, Greek Goddess of the Hunt. The irony came from the fact that Artemis was also one of the virgin goddesses, yet the costume was quite revealing.

Quentin bit back a disapproving-fatherly reaction and lightly smacked both Rene and Rory on the backs of their heads when he noticed they were staring. Worse, the girls seemed more amused by the men's reactions than anything else.

"Are you guys not done yet?" Barry asked as he and Iris walked into the Cortex, dressed as zombie tourists with blood-smeared, tacky Hawaiian shirts. They were greeted with the sight of Cisco Ramon, wearing a long black coat, black pants, and black shades, trying to stay balanced on a chair while holding up some black and orange streamers. Wally, dressed in a Racecar Driver's suit, was similarly perched several feet away (his helmet sitting on a nearby table), though he was having better luck in the balance department. A box full of Halloween decorations showed how little progress they were making.

Standing in the middle of the room was Caitlin, in a classic witch costume, calling directions to them. "Raise your end two inches higher, Cisco."

Cisco struggled to do so, but he was already standing on his toes and stretching his arm as high as he could. "I'm trying! This would go a lot faster if we had a little help!"

Barry rolled his eyes and zipped around the room, pulling Wally and Cisco safely off their chairs before putting up all the decorations themselves. "There!" he announced when he was done.

Wally and Iris looked around, pleased with the way Team Flash's command centre now looked. Cisco was grinning even as he complained: "You couldn't have gotten here an hour ago?"

Caitlin, however, frowned slightly. "I kind of wanted the big spider over there." Barry rolled his eyes again, moving the large decoration to where she wanted it. "And the pumpkin-"

"It looks great, Barry," Iris interrupted, "Really."

"Oh, come on, we've had to deal with her for an hour," Cisco complained, "Now it's Barry's turn."

Caitlin gave him a dirty look. "And what, exactly, do you mean by that, 'Neo'?"

Cisco edged away from her and tried to stammer out an excuse, but was saved by a voice calling out from the entrance. "Happy Halloween, Team Flash!"

All turned to see a few familiar faces – and some new ones – as the self-dubbed 'Legends' entered the room. Ray, the one who'd spoken, waved happily at them.

"Hey, guys!" Cisco greeted them, grateful for the distraction. "Welcome to the party! You're the first ones here."

"I'm guessing you're Cisco?" the blonde dressed as a cowgirl asked, "Sara Lance."

"Right, hi!" He shook her offered hand, briefly turning serious. "I'm so sorry about Laurel. Really, she was a friend to a lot of us here."

There was a bit of milling around, introducing Sara, Nate, and Amaya to the various members of Team Flash, and introducing Wally to the Legends (as he'd never met any of them). Mick sort of hovered by the exit, until Amaya noticed. "I'm guessing you don't get along with these people?" she asked.

The present members of Team Flash nervously looked in his direction. "Is it safe to have him here?" Caitlin asked nervously.

"It's cool," Ray assured her, "He's with us, now."

"What did you do to them?" Amaya asked softly as she took in their skepticism.

Mick grunted and shrugged. "Kidnapped a couple of 'em, mostly." He looked over at Cisco. "How's that brother of yours?"

"Dead," Cisco replied hollowly, "Car crash. How's that partner of yours?"

"Dead. Got himself killed saving us all."

"Oh."

And it was this awkward silence that greeted Joe and HR when they entered the room. "Woah," HR commented, "What's with all the sad faces? I thought parties were happy events on this Earth, too."

"They are," Stein said, trying to break the tension, "Some of us have just had to deliver some bad news. You must be Harrison Wells of Earth-2."

Behind him, Amaya and Nate both mouthed "Earth-2?" with very confused looks on their faces.

"Earth-19, actually," Joe corrected him, "Harry had to go home; Zoom did a lot of damage on his Earth that still needs to be fixed. And someone had better give me a good reason not to arrest him."

"Because he is a vital member of our team," Sara immediately answered, "and we do very important work, protecting history itself, and you'd have to go through the rest of us first, which nobody here wants."

Joe sighed, but seemed to agree to go with that, for now.

"Sherlock Holmes again, Dad?" Iris asked, searching for a new topic of conversation.

"Again?" Wally questioned.

"He's been going as Sherlock Holmes for years," Barry explained, "We can never talk him into picking a different costume."

"And who, exactly, am I supposed to be, again?" HR questioned.

"Albert Einstein," Ray answered, as if it were obvious, "You know, the greatest scientific genius in history?"

"Huh. On my Earth, it's a man named Max Schreck."

"The guy from Nosferatu?" Jax questioned.

"We met Einstein," Mick piped up before HR could ask what Nosferatu was, "The Professor here punched him in the face." Stein looked up and scowled, having heard his name while trying to explain Infinite Earths to his teammates.

"It was a complicated situation," he defended.

"You punched Albert Einstein?!" Caitlin gasped.

"Now that is a story I want to hear." Thea came up from behind Joe, leading Quentin and her brother's new recruits. "Hi, Ray! Hi, Sara!"

"Hey, Speedy," Sara greeted her as she gave the younger woman a hug.

"Actually, I've retired from the vigilante life, so I am no longer Speedy."

"Thea, kiddo, you were Speedy when you were practically still a toddler, you're still Speedy to everyone who knew you back then. Hi Daddy!" She then ran over to hug her father.

"Hi, Baby."

As father and daughter caught up, Barry took it upon himself to greet the new vigilantes. "Hi, I'm Barry Allen."

Evelyn shook his hand first. "Evelyn Sharp. You're the Flash?"

"No offense," Rory added, "But I think we were expecting you to be a bit…"

"Taller?" Barry suggested, "Bigger? Older? Believe me, I have heard jokes about people saying I look younger than I actually am."

"Oh, I get that. I'm thirty-two and I still get carded. I'm Rory Regan, by the way."

Rene stepped forward as well and introduced himself. "If I knew running around Star City in a hockey mask was going to get me introduced to the Flash, I would've started it a lot sooner." His teammates immediately began teasing him about having a fan-crush on the Flash.

On the other side of the room, Wally had cued up some music to try and chase the last of the awkwardness away – like HR said, parties were supposed to be happy events – and Caitlin and Iris started bringing out the punch bowl and snacks. The room was soon filled with chatter as all three groups started mingling, although Mick tended to hang closer to his teammates and stay on the opposite side of the room from Joe and Quentin.

Stories were swapped, of metahumans faced and criminals captured, and time periods visited – the Legends all seemed to be having a ball, telling everyone about the times and places they'd been to. Stein and Cisco left partway through to head to his house – apparently Cisco had once again volunteered to help Clarissa with the Steins' 'haunted house'.

Looking around, one could see Amaya talking with Barry about her Tantu totem, her eyes wide as he told her about the woman who was probably her future granddaughter. Sara was entertaining the New Team Arrow with some less-than-flattering moments from Oliver's high school years – not so much his issues with fidelity, but silly stories that would have him sputtering in embarrassment if they were ever brought up. HR bounded from group to group, constantly pestering them about what was different on their Earth and telling them about his own, but thankfully they were mostly more amused than annoyed. Mick was one exception, threatening to shove his authentic shuriken up somewhere unpleasant, only for Amaya to step in and veto that idea ("Do you have any idea how long it took me to find that thing? In the dark?!").

Overall, the S.T.A.R. Labs party was a success. Fate seemed to be smiling down on them, as for once, no metahuman alerts came in, no emergencies that the Flash would have to deal with. For one day, the heroes were able to just relax and have some fun.

THE END

I hope you all liked it! I had a hard time deciding what costumes to give Team Flash, as I sort of had a theme going for the other groups (references to hero IDs for Team Arrow and tributes to past eras visited for the Legends). Although I also wasn't sure what to dress Mick up as, and then I watched 'Shogun', and... well, who knew there was something in history for Mick to geek out about? Ray's costume came from something Nate mentions in the beginning of this season's premiere. HR dressing as Einstein just felt like a good excuse to bring up Stein punching out Einstein. Also, although it wasn't mentioned, you can bet Cisco jokingly suggested that Caitlin dress up as Elsa from Frozen - but with her new ice powers emerging and terrifying the hell out of her, there was no way that was happening.

Max Schreck was the actor in the classic German vampire silent film 'Nosferatu' - I just thought it would be funny if the genius on Earth-19 was someone other than Einstein, so I looked up famous people who were born in the same year as Einstein and picked Schreck. Should be no weirder than Captain Singh being a criminal and Deadshot being a cop.

The references to the Steins' Haunted House come from a year-old entry in Cisco's character blog 'The Chronicles of Cisco' on Tumblr.

One last thing: I have no idea how old Rory is, but I was rather surprised to find out that his actor was born in December 1983, meaning he is 32 years old.