Kate Lethbridge-Stewart & UNIT return to 'Doctor Who' as series jumps to Disney+ next season

You won't need to hop into a TARDIS and travel back in time to catch new Doctor Who episodes featuring the fictional military organization UNIT. That also goes for Kate Stewart, who leads the group's scientific research department. The long-running sci-fi show confirmed actress Jemma Redgrave will return to the show as Kate, and also added that Aneurin Barnard is joining the cast.

In a "cast announcements" tweet, the official Doctor Who twitter account run by BBC wrote: "UNIT returns! Jemma Redgrave returns as Kate Lethbridge-Stewart, and UNIT, the long-running organization set on defending the Earth, returns in the next series of #DoctorWho. Aneurin Barnard also joins the series as the mysterious Roger ap Gwilliam."

No other details were released. Redgrave, 57, was first cast in the series in 2012, and has recurred in the role, including in a 50th anniversary special in 2013, episodes in 2014 and 2015, as well as in episodes from 2021, on. Welsh actor Barnard, 35, has previously appeared in the films Dunkirk and The Goldfinch, as well as the mystery sci-fi show 1899, which was recently cancelled by Netflix after just one season.

The long-running favorite returns later this year, but fans will no longer be able to watch it on the BBC. In October, it was announced that Doctor Who was moving over to Disney+ for its upcoming seasons. Ncuti Gatwa, of the Netflix comedy-drama show Sex Education, is set to be the 15th Doctor. He'll make history as the first black actor to hold the series' leading role when his first episode airs somewhere around the end of this year.

But before that, David Tennant — who held the lead role as the Tenth Doctor incarnation — will be back as the Fourteenth Doctor for a trio of 60th anniversary special episodes set to air in November.

Gear up for new Doctor Who episodes with other alien adventures in SYFY's Resident Alien, now streaming on Peacock.