The War Between the Land and the Sea: Release date speculation for Doctor Who spin-off

Fans of Doctor Who will have to wait a while for the next season of the show but, in the meantime, there's an exciting new spin-off on the way.

Unlike Torchwood or The Sarah Jane Adventures, the upcoming miniseries The War Between the Land and the Sea is a five-part standalone story. It's also the first full Doctor Who spin-off since 2016's Class, tying into the new era of the Doctor Who franchise.

Starring Russell Tovey and Gugu Mbatha-Raw alongside several recurring Doctor Who actors, The War Between the Land and the Sea was created by Doctor Who showrunner Russell T Davies, working with longtime Doctor Who writer Pete McTighe.

But what is this show about, and when can we expect to watch it? Here's everything we know so far.

When will The War Between the Land and the Sea be released?

The War Between the Land and the Sea will air in 2026, although the specific release date hasn't been confirmed yet.

Speaking at Edinburgh TV Festival in August 2025, the BBC's director of content, Kate Phillips, mentioned that The War Between The Land and the Sea will arrive "next year."

This release window is later than fans might have expected, as the show wrapped filming in December 2024, and Doctor Who magazine previously reported that it would come out in 2025.

What will The War Between the Land and the Sea be about?

Taking place in the Whoniverse, this miniseries will feature familiar characters from from the UK government agency UNIT, but it isn't expected to include the Doctor. In fact, it's specifically pitched as a story about how humanity copes with a disaster when the Doctor isn't around to help.

The BBC's official synopsis reads: "When a fearsome and ancient species emerges from the ocean, dramatically revealing themselves to humanity, an international crisis is triggered. With the entire population at risk, UNIT step into action as the land and sea wage war."

This story will feature the Sea Devils, a classic Doctor Who creature that first appeared in 1972, and returned in 2022 for the Thirteenth Doctor episode The Legend of the Sea Devils.

Speaking at San Diego Comic-Con in 2024, Russell T Davies explained, "There's a race that lives beneath the oceans, they wake up and they see the state of the oceans that we have put it in. We have wrecked the place, and it is war. And it's war on an epic scale." Climate change will apparently be a key theme in the story.

At the Edinburgh TV Festival in 2025, lead actor Russell Tovey said, "You can expect heart palpitations. You can expect love. Again, I keep going back to that, it's driven by love. This guy [Tovey's character Barclay] loves his life, loves his family, and will do anything to protect them. You're going to be moved and entertained with this."

Highlighting the contrast between this spin-off and the typical format for Doctor Who stories, he added, "It's set in this world and this force comes upon us. I feel like that's different, in some ways, to the way that Doctor Who has been before, because it's always [us] visiting them, whereas this is like Independence Day."

Who will star in The War Between the Land and the Sea?

Russell Tovey will star as the drama's everyman protagonist Barclay, alongside Gugu Mbatha-Raw as a Sea Devil character named Salt, a role involving extensive prosthetics. Both actors have appeared in the Doctor Who franchise before, but this time they're playing new characters with no relation to their previous roles.

Thanks to UNIT's central role in the story, we're going to see several familiar faces from Doctor Who, including the characters Kate Lethbridge-Stewart (Jemma Redgrave) Colonel Ibrahim (Alexander Devrient), and Shirley Ann Bingham (Ruth Madeley).

Another returning character is more of a deep cut: General Austin Pierce (Colin McFarlane), who previously appeared in the 2009 miniseries Torchwood: Children of Earth.

The cast will also include Adrian Lukis, Patrick Baladi, Francesca Corney, Mei Mac, Vincent Franklin, Waleed Hammad, Iestyn Arwel, Hannah Donaldson, Manpreet Bachu and Ann Akinjirin – all currently playing undisclosed roles.

There's obviously a lot of speculation about potential cameos from other Doctor Who stars, but we're not expecting to see Ncuti Gatwa (or Billie Piper) during the gap between seasons fifteen and sixteen of the main show.

Is there a trailer for The War Between the Land and the Sea?

There is! A short teaser was released following the last Doctor Who season finale, but right now we're still waiting for a full-length trailer to arrive.

The War Between the Land and the Sea will air on BBC One on BBC iPlayer.

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