Russell Tovey and Gugu Mbatha-Raw will star in a Doctor Who spin-off called The War Between The Land And The Sea, it has been announced.

They will lead the cast alongside Jemma Redgrave and Alexander Devrient in the series, which was created by Doctor Who showrunner Russell T Davies.

He has written the series with Pete McTighe, who has also worked on Doctor Who.

Plaza Suite gala performance
Russell Tovey (Yui Mok/PA)

Redgrave and Devrient are also no strangers to the sci-fi series, and Redgrave will reprise her role as Kate Lethbridge-Stewart, Head of Scientific Research and Commander-in-Chief at UNIT, from the main show. Devrient will reprise his role as Colonel Ibrahim.

The action begins when a fearsome and ancient species emerges from the ocean, dramatically revealing themselves to humanity, and triggering an international crisis. With the entire population at risk, UNIT step into action as the land and sea wage war.

The series was announced by the BBC and Disney, which airs the show outside of the UK on Disney+, at San Diego Comic-Con.

Love and Friendship UK Premiere – London
Jemma Redgrave (Ian West/PA)

Tovey, who is best known for roles in Being Human, Feud and Looking, will lead the show alongside Mbatha-Raw, who found fame in Belle and Beyond The Lights and has since starred in The Morning Show and Loki.

Davies said: “I’m so lucky to work with such a magnificent cast. And this is a huge, muscular, thrilling drama which will shake The Whoniverse to its foundations.

“When the Doctor’s not in town, the whole of humanity is in trouble.”

Lift photocall – London
Gugu Mbatha-Raw (Ian West/PA)

Lindsay Salt, director of drama at the BBC, added: “The War Between The Land and The Sea is another utterly unique and gripping drama from Russell T Davies and we’re delighted to welcome the show to The Whoniverse.

“Featuring a stellar cast, with Russell Tovey and Gugu Mbatha-Raw taking on leading roles, this brand new, epic, mini-series will leave audiences on the edge of their seats as they watch UNIT take on one of their biggest battles to save humanity.”

Filming on the show begins next month and will be directed by Dylan Holmes-Williams, who has previously directed episodes of Doctor Who.

The series will air on BBC One and BBC iPlayer in the UK, and on Disney+ outside of the UK where available.