Takes place after Season 4, but before Season 5. This is going to be a mostly canon story, with only slight AU - (WARNING: Season 4 Finale spoiler ahead) Behrad doesn't replace Zari after Nate is revived. Behrad was instead killed in a mugging, and Zari and the Legends tracked down the mugger and got back the amulet in Season 3 (instead of breaking into the ARGUS facility). Also, none of the Nate/Zari stuff happened (because that was just weird; honestly, there was no chemistry there beyond friendship).
Credit for this idea goes to 93MANIAC, as they approached me and requested this story.
"Captain, we have a magical alert," Gideon's voice rang through the intercom in the kitchen, where Sara and Ava were just sitting down to eat breakfast.
"Ugh, every time," Ava grunted.
Sara gave her a wolfish grin. "Sorry my love, but duty calls." She gave Ava a peck on the cheek before twirling away, tapping her ear to activate the comms as she exited the kitchen and made her way to the bridge.
Zari was in the middle of an intense Smash Bros battle with Nate when Sara's voice sounded through the comms, alerting the Legends and ordering them to the bridge. Zari doubled down and quickly disposed of Nate's character just as the time limit on the fight wore out.
"Aw, come on, that's cheating!" But Nate's protests fell on deaf ears as Zari tapped him on the head and exited the room. Nate got up and followed.
Upon arriving to the bridge, she found Mick and Sara in the middle of a heated argument, while a sleepy Charlie, with a bowl of popcorn fabricated by Gideon, and Ray, who was entirely too cheery for the morning, both watched, not daring to intervene.
Zari walked over to Charlie and Ray. "What's going on?" she stage-whispered.
"Mick's angry about having to wake up early for a mission. Apparently he got back from Aruba late last night or something. Personally, I don't know why he's upset. We have a mission, and those are always fun!" Ray piped up cheerily.
"Don't listen to Rayge. He's clearly delusional from finally getting some action with Darhk," Charlie added, earning a few sounds of protest from Ray.
A moment later, a pair of arms wrapped around Ray's midsection from behind. "Why so indignant? She's right, you silly dope." Ray shifted to bring Nora in front of him, wrapping his arms around her in turn before kissing her on the forehead, while Charlie and Zari made noises of feigned disgust. Nate gave Ray a fistbump over Nora's head, and she rolled her eyes before untangling herself from Ray to talk to the other girls.
Zari stole some of Charlie's popcorn as they turned back to the fight still raging in Sara's office.
"I don't care how tired you are, Mick! You're still going on this mission! So you can either suck it up and join us, or you can quarterback, and you will not slack off and nap if you quarterback, or so help me, I will make Gideon play ABBA music in your room for a month!"
"This is stupid! I thought we were done catching creatures after that stunt at Pretty Boy's park or whatever anyway!" Rory roared back.
"Well, actually," Ray piped up, while Nora face-palmed. "if you'd been here a week ago, you'd know that the Time Bureau tasked us with tracking down the rest of the magical creatures and give them the option of either rehabilitating them in an uninhabited place, or giving them a place at Heyworld." Ray had a very satisfied smile on his face, until Nora smacked his shoulder.
Mick glared back at Ray. "Didn't ask you, Haircut!"
"Hey, it's not his fault you decided to go gallivanting around Aruba. Again," Sara reminded him.
Mick grunted. "Yeah, whatever," he conceded. "But I'm not quarterbacking!"
Sara gave a saccharine grin. "Fine by me. Nora, do you want to quarterback, or do you want to go out in the field?
Nora started. "I get to pick?" Sara nodded in confirmation. "Well, then I want to go in the field. I did great field work for the two entire days I was in the Bureau."
"Sounds good. That means Ray is quarterbacking," Sara declared.
"Hey, wait a minute. Why does that mean Ray's quarterbacking? Don't split up the Time Bros! We just got back together!" Nate protested on Ray's behalf, clapping a hand on his shoulder in a show of support.
"Because I'm not putting both of them in the field on the same mission until I know that they won't get distracted," Sara explained. "Especially because our fugitive is a siren, so we need to split up couples."
"Wait, don't sirens make you see visions of whoever you're attracted to? Wouldn't it make more sense to have couples on the mission?" Ray interjected.
Sara waved Charlie over to present. Charlie took a tablet from off of the desk, and began swiping and tapping on it, eventually pulling up a few images on the device, which Charlie held up to show everybody. "Not this one. This bloke, Syron, amps up the attraction between two people near each other, like an aphrodisiac. Can't do anything if you don't have any chemistry with anyone nearby, so couples have to split up for this one. Much more dangerous, if you ask me, using your loved ones against you. Bloody bastard."
"Well, let's hurry up and roast this pig so I can go back to bed," Mick stated gruffly.
"You heard the man, let's move out!" Sara called as everyone made their way out of the office and over to the seats at the front of the ship. "Gideon, plot a course."
"Right away, Captain."
They arrived just outside of a moderately sized town in France in May of 1739. The Waverider had landed in a large clearing in a forest just outside of the town's borders, and Sara quickly put up the cloaking for the ship.
"Alright, so this fugitive has been sneaking into the homes of newlyweds, charming them so they're completely distracted, and then robbing them blind," Sara started.
"Sounds like my kind of guy," Mick interrupted. Sara rolled her eyes, but her smirk betrayed her amusement.
"Anyway, here's the plan: Nate and Nora will go undercover as a couple. They will be renting one of the vacant homes in this town, and tomorrow, they will throw a housewarming party. The rest of us will pose as their friends and family at the party, and will help sell the idea that they are wealthy newlyweds to the rest of the town. Everyone will be invited, so Syron should be there too. If we figure out who he is at the party, that's great. If not, no worries; we'll be waiting when he comes back to steal all the stuff that we're going to stage for the party. Gideon will fabricate what we need for that. We'll capture the siren, and boom! We'll be on our way out of France." Sara's plan seemed solid, and was actually really thought out. There was even a contingency option. Zari raised her eyebrows at Sara, as did Charlie and Nora. "Alright, I'll admit, Ava helped me a little with the plan." Zari and Charlie chuckled, and Nora smiled fondly at the mention of her friend, Ava.
"Ray, we're going to set up some small cameras in the house, so you'll be able to see everything from here. If you see anyone suspicious during the party, let us know and we'll investigate. In the meantime, I want you to take a closer look at Charlie's compiled research to try to get a better idea of who this guy is," Sara directed.
"Aye aye, Captain," Ray replied with a mock salute.
"At ease, soldier. The rest of you, to the fabrication room. Nate and Nora will go first, taking the fabricated money to the landlord and getting the key to the house, and also renting a horse and wagon. The rest of us will be fabricating furniture, which we will shrink for more room, and 'valuable items', which we will put into the wagon when they return and cover with a tarp so no one sees the shrunken items. Then we'll do the move-in. While we ride past in the wagon, we'll announce the party tomorrow to the pedestrians, who will probably tell the rest of the town. We'll leave Nora and Nate for the night, to sell the idea of them being newlyweds, and get a room at the inn across the street, which will be our vantage point to look for any suspicious activity during the night, just in case our fugitive shows up ahead of schedule. Now, let's move out!"