‘Arrow’/’The Flash’ Spin-Off Cast Grows, Adds ‘Doctor Who’ Alum

Arthur Darvill in 2013 (Getty)

It’s still only in development, but the cast of the “Arrow”/”The Flash” spin-off is growing.

Joining Wentworth Miller (Captain Cold/Leonard Snart), Brandon Routh (The Atom/Ray Palmer), Victor Garber (Prof. Stein), Dominic Purcell (Heat Wave/Mick Rory) and Caity Lotz (in an unnamed role) are “Doctor Who” alum Arthur Darvill and actress Ciara Renee.

Arthur will play Rip Hunter, in a series regular role of a time traveler, who uses his charm to hide the fact that he’s responsible for history.

WATCH: ‘The Flash’: Grant Gustin On Working With Original Trickster Mark Hamill

Ciara will play Kendra Saunders, aka Hawkgirl, a name that stems from one of her past lives as an ancient warrior.

Earlier this month, one of the executive producers on the project, Greg Berlanti, discussed how producers deal with making a spin-off without hurting the mothership shows.

WATCH: Victor Garber On ‘Flash’/‘Arrow’ Spinoff

“They’re all unique in their own way. ‘Arrow’ is sort of a crime/family saga and ‘Flash’ is sort of a part family drama, part cop show, part sci-fi extravaganza, and the team up show has its own identity too. And I think that’s the thing, is not thinking of them as all similar superhero shows with characters that are from the other universes, but actually their own, distinct universes and their own distinct tones and worlds and I think that’s the key. Otherwise, if you’re doing it just to do it, it’s too hard and it’s a lot less fun,” he told Access.

— Jolie Lash