Captain Cold (Wentworth Miller) has had a long and interesting history in the Arrowverse, and after a prolonged absence he's now set to return to Legends of Tomorrow for at least a few more episodes, but he's not committed beyond the end of this season. Leonard Snart started out as a Rogue on The Flash, but quickly graduated from freak-of-the-week to show regular. Over the next seasons, Leo developed into a sassy thief with a heart, with several episodes exploring his backstory and how he (and his sister) ended up working with Mick Rory (Dominic Purcell) in Central City. By the time Captain Cold made the leap from Rogue to Legend, he was almost a real hero.
As a time-traveller, Cold climbed to new heights as a fan favorite. The perfectly brilliant foil to Mick Rory's brute force, he was always ready with a snarky one-liner and a willingness to steal things. His position as a fan-favorite made his eventual death all the more heartbreaking... as did his decision to sacrifice himself to save the team. From selfish villain to sacrificing hero, Leonard Snart was one of the best characters in the Arrowverse; and thankfully, death doesn't mean a whole lot on the CW. Since he 'officially' died at the end of season 1 of Legends of Tomorrow, Snart has returned several times in different ways. Past versions of the character have popped up across The Flash and Legends of Tomorrow, and now it seems that a doppelganger has rejoined the team thanks to Crisis on Earth X.
Crisis On Earth X: Captain Cold's Return
Leonard Snart made his reappearance on Earth X last week, as a hero with the same name and abilities, but a few key differences. He prefers to be called 'Leo' for one thing, and uses Citizen Cold as his superhero name for another. This version is also openly gay, and found the Arrowverse team when he swooped in to save his boyfriend, The Ray (Russell Tovey), from a Nazi internment camp run by Earth X's Quentin Lance (Paul Blackthorne). Turns out, Leo is moved by Team Arrowverse's plight, and becomes one of the only Earth X heroes willing to help them get back to their own world and save their friends.
After both Leo and Ray head to Earth-1 in order to help save the day, Citizen Cold makes an interesting decision. During the wrap-up of the four parter, when everyone is getting back to their lives, rather than return home with his boyfriend, Leo decides to stick around on Earth-1 for a little while. Ray heads back thanks to a breach opened by Cisco (which means that Snart can follow him whenever he chooses), and Leo leaves him with a kiss and a promise... and without any real explanation as to why he's staying put. He also doesn't reveal how long he's going to be visiting the main Arrowverse, either, but fans of the character are hoping that he'll be here for a while.
Wentworth Miller's Contract With The CW Ends
Unfortunately, it seems that this latest visit by Cold is another short one. Although Wentworth Miller went from recurring character to season regular when he became a Legend, he went back to recurring character for the past season and a half. His post-death appearances have been achieved primarily by time-travel and alternate universes, and while he had a relatively large role in Legends of Tomorrow season 2's Legion of Doom arc, it seems that Citizen Cold is going to be his last hurrah as the character. On November 4th, Miller posted to Instagram, confirming that he was filming his 'final scenes' as the character. He hasn't confirmed how many more episodes of Legends of Tomorrow he has left, but it's a safe bet that his exit means Leo will return to Earth-X... or meet a sticky end... by the end of the season.
This doesn't mean that Miller can never return to this universe, of course. What it does mean is that his regular contract with the CW is over at the end of this season; as a regular or recurring character. Miller has given no specific reason for his exit from Legends Of Tomorrow (unlike co-star Victor Garber, who left to perform on Broadway), and does not currently have any new projects confirmed to be in the works. However, the actor has been focusing on art on his Instagram recently, posting and promoting various artists, as well as showcasing his own work, so he may be taking a break from screen to work on canvas.