DISCLAIMER: "D.C.'s Legends of Tomorrow" is the property of D.C. Entertainment. I'll put all the characters back where I found them, promise.

AUTHOR'S NOTE: This is my first published fic in a long. long time, and my first one set in the Arrowverse. Series compliant through 1x09 "Left Behind," then it goes a bit off the rails! More author's notes below.

CHAPTER 1

-August 23, 2063 - Waverider Medbay-

"I know this sounds weird, but for once, Vandal Savage did us a favor," Ray said, sliding off the Medbay bed after Gideon pronounced him fit. He landed awkwardly and stumbled a little, until Rip steadied him.

On the second bed, Snart rolled his eyes. "You would be an optimist about this," he growled.

Ray shrugged. "He didn't kill us."

Snart fixed him with a glare. "He didn't kill us because he was too busy killing his turncoat minion first!"

Unfazed, Ray went on, "Well, the team would never have found us if he hadn't set off that explosion."

"If you hadn't noticed, that explosion destroyed the one thing that could fix this mess!" Snart shot back.

"I don't suppose this is a good time to tell you your Cold Gun got busted, too?" Jax asked.

"It just gets better and better!" Snart groaned. He stood carefully and looked over the damage.

Aches and pains and soot and some weird orange goo all over. His arms were wrong. His hands were wrong. Hell, everything was wrong. Walking across the room gave him an awkward feeling he hadn't had since his first teenaged growth spurt, but he shrugged off Stein's attempt to help him.

And then there was that wounded puppy expression on his face…

A face Ray Palmer was currently wearing.

-August 22, 2063, Waverider Bridge-

They had a fix on Savage in San Diego, where he had a hilltop mansion and a majority stake in a biotech company that had recently begun work on biological weapons.

"I thought those were against the Geneva Convention or something?" Jax asked as the team gathered around the holo table.

"Since when has that stopped anyone?" Mick snorted. "Even before the Time Masters trained me, I knew that promises were meant to be broken and deals don't mean a damned thing." The last sentence came out as a growl, and he stared fiercely across the table at his onetime partner.

This was one of those days when Snart didn't think Gideon's careful weeks of deprogramming would hold. That stare was as searing as the flames of the heat gun Rip still kept locked away out of Mick's reach. This might be the day they had to use the trigger word planted as a post-hypnotic suggestion in Mick's brain. It would cut him down like a massive tree, so they could lock him up again and start over. Snart drew in a breath, the word at the tip of his tongue, just in case.

Then Rip cleared his throat, drawing Mick's gaze away. The big man relaxed, and Snart let his breath out again.

"Leaving cynicism aside," Rip said, "Savage's puppets in Congress disavowed the Convention last year, just before he took over LJ BioGene. Three years from now, the company will produce a superbug version of Creutzfeldt-Jakob disease, which Savage will put into the water supplies of communities that oppose him. Millions will die, but they'll go insane first."

"Poisoning the wells with a mutated version of mad cow disease," Stein breathed. Rip nodded grimly in response.

"Wait a second," Ray interrupted. "LJ BioGene? I know those people." He stopped and corrected himself. "I knew those people. They were researching the immune system and human longevity fifty years ago."

"And they still were last year," Gideon interjected. A Wall Street Journal article, including a picture of Savage, appeared on the holo display. "But after the takeover, Savage told a shareholders meeting that the company's resources would be redirected to more profitable enterprises."

"Like making superbugs," Jax said.

Ray shook his head in disgust. "Have to make the shareholders happy."

"Always more money to be made in killing people than in making them live longer," Snart said dryly.

"And Savage probably doesn't want any competition in the immortality game," Sara observed. She glanced over at Rip. "Remember that ritual back in 1975?"

The Captain frowned as Kendra winced. During the ritual, Savage drained the blood from Carter Hall's body into a chalice, which he passed around to his followers. He claimed one sip would give them an extra hundred or so years of life.

"An alternate source of near-immortality could make his followers less loyal," Rip conceded. "Savage needs his army to succeed. Even an immortal can't take over the world all on his own, whether or not he's armed with a deadly disease."

"Attila had to have his Huns," Jax said. He looked at the raised eyebrows all around him. "What? I liked European History. The teacher was cool."

Rip smiled slightly. "Your history books didn't tell you that Savage was Attila."

"Quite the curriculum vitae," Stein said derisively.

Kendra's eyes widened. "I'd forgotten that," she murmured. Then, in a louder voice, she said, "Savage chased us all over Europe. He finally caught up to us in northern Italy, near Venice. His army sacked our town while he killed us, again."

Ray clasped Kendra's hand as the team stood in silence for a moment. But only for a moment. Quiet reflection wasn't Snart's style, and he broke the silence impatiently. "Now that we've had our history lesson for the day, what's the plan?"

"Oh, you'll like it, Mr. Snart," Rip said, his slight smile returning. "It calls for lots of breaking and entering."

-August 23, 2063 - Waverider Medbay-

Rip pinched the bridge of his nose. He had a whopper of a headache coming on, and Gideon's explanation of the predicament wasn't helping any.

"I cannot detect any sign of brain damage," the AI reported. "Physiologically, both Dr. Palmer and Mr. Snart are fine."

"But this isn't a physiological problem," Professor Stein objected. "From what they are telling us, this is a matter of mind. Their minds have been exchanged."

"Sounds like a bad 'Star Trek' episode," Jax said as Kendra ran into the Medbay, heading straight for what she thought was her boyfriend's side until he held up a hand to stop her.

"Not that I don't like you, Kendra," he said. The voice was Ray's, but the intonation was all Leonard Snart, an icy drawl. "But I'm not the man you think I am."

Kendra looked around in confusion. "I don't understand. Ray, that doesn't sound like you at all."

"That's because he's not Ray," Rip said. "He and Mr. Snart became human guinea pigs for a… what did you call it again?"

"A Soul Swapper," Ray offered helpfully.

Kendra stepped back from the man she thought was Ray. "So you're…"

"Captain Cold at your service," Snart answered, inclining his head slightly. "I've taken a lot of things that weren't mine, but this one tops 'em all. Although it wasn't really my heist."

Kendra looked stunned. "What are we going to do?"

"We'll figure something out," Stein soothed. "We always do."

"Either that," Ray said, "or our relationship is going to get more complicated than it already is."

ADDITIONAL AUTHOR'S NOTES: This story was inspired by an answer given during the "Legends of Tomorrow" panel at WonderCon in Los Angeles on March 27, 2016. The actors were asked whom they'd want to play if they could play any other Legend, and Brandon Routh's answer was, "Captain Cold." It got me to thinking what that might look like, and I started writing just before the airing of 1x10 "Progeny." Any similarity to that episode's storyline is not intentional; it came as a big surprise to me. (So did the quick resolution of the Mick Rory problem, and I still haven't bought it.)

Historical note: Attila the Hun terrorized Europe for a brief but bloody nine year period, which included the razing of the Italian town of Aquileia one year before his death.

Pop culture note: Jax is right; this was the plot of a bad Star Trek episode. "Turnabout Intruder" is considered one of the two worst original series episodes.