The Doctor Who franchise is about to get even bigger with a new spinoff series that, interestingly, doesn’t seem like it’s going to focus on everyone’s favorite Time Lord.

During the Doctor Who panel at this year’s San Diego Comic-Con, Disney and the BBC announced that The War Between The Land And The Sea — a new series written by Russell T. Davies and Pete McTighe — is on the way. Rather than the Doctor, the new show will revolve around a group of humans as they work together to face the Sea Devils, a race of ancient, ocean-dwelling creatures who first appeared in Doctor Who back in 1972.

Jemma Redgrave and Alexander Devrient are set to reprise their roles as Kate Lethbridge-Stewart and Colonel Ibrahim, respectively, but they will also be joined by Russell Tovey and Gugu Mbatha-Raw as characters not yet revealed. Previously, Tovey and Mbatha-Raw both starred in Doctor Who —he as Titanic midshipman Alonso Frame, and she as Tish Jones — but it’s not clear whether that’s who they’ll be playing here.

In a press release about the new show, Davies called it “a huge, muscular, thrilling drama which will shake The Whoniverse to its foundations,” and while we don’t know when to expect its debut, it’s scheduled to begin shooting in August.