On Jan. 21, The CW will debut the Arrow and The Flash spin-off DC's Legends of Tomorrow, a new series that's bigger than anything the network has ever done before. Featuring a never-before-seen team-up of comic book characters like the Atom (Brandon Routh), White Canary (Caity Lotz), Captain Cold (Wentworth Miller) and Firestorm (Victor Garber and Franz Drameh) taking on the immortal villain Vandal Savage (Casper Crump), the series is more campy than either of its parent series and fully embraces its comic book origins to tell a story about destiny, time travel, and the future of mankind.

The series won't have too much overlap with either of its parent series, though, thanks to its time-traveling nature, which is made possible thanks to the character Rip Hunter (Doctor Who's Arthur Darvill), a Time Master who recruits the show's various heroes and villains to take on Savage. "It's intermittent throughout," executive producer Greg Berlanti said at the Television Critics Association's winter previews on Sunday. "Because they're a band of time-traveling rogues, it's harder for Arrow and Flash to be connected story-wise to it throughout the season. That being said, if you know the histories of Arrow and Flash, it should be extra-fun in its own way as we delve deeper and deeper into the characters' lives."

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But how will the series handle the complexities inherent to time travel? "We try and exist by the rules we establish for ourselves," said Berlanti. "Our real goal in all of it is to make something emotionally true and truthful for the characters. That being said, whenever we have conversations about time travel in the [writers'] room, I always ask my questions in terms of, 'Is this like Back to the Future? Or is it like 12 Monkeys?' and use other examples that have pre-existed."

He continued, "As [executive producer] Andrew [Kreisberg] always says, as far as we know, time travel is not real. If there were an actual rule book we could read and learn from, we could follow that. We try and follow whatever rules we establish for ourselves. Because we have the advantage of all of these characters learning about it as they go along, we're hoping that as we go along and we kind of establish these rules for ourselves, some of which we have pre-established on The Flash, that the audience is learning it too."

DC's Legends of Tomorrow premieres Thursday, Jan. 21 at 8/7c on The CW.