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

We're still just over a year away from Doctor Who returning for its 2026 Christmas special, but thankfully, fans have got a brand-new spin-off series arriving to tide them over until then.

The War Between the Land and the Sea, a five-part standalone miniseries, follows on from previous spin-offs such as Torchwood, The Sarah Jane Adventures and Class, and features a number of returning stars in both new and existing roles.

Starring Russell Tovey, Gugu Mbatha-Raw and Jemma Redgrave among others, the series has been created by Doctor Who showrunner Russell T Davies and longtime Doctor Who writer Pete McTighe – and the latter has teased we will see plenty of Easter eggs tying it to that show's history.

Speaking exclusively with RadioTimes.com, McTighe said: "There are absolutely Easter eggs to be seen – if you get the pause button ready, you'll be seeing plenty of stuff."

But what is The War Between the Land and the Sea 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 start airing on BBC One and BBC iPlayer at 8:30pm on Sunday 7th December 2025.

Episodes 1 and 2 will air back to back, with episodes 3 and 4 airing and week later, and episode 5, the finale, airing on its own the week after that. For international viewers, it will arrive on Disney Plus at some point in 2026.

Speculation on the release date for the series has gone back and forth, with it once being announced the series would air next year. It was finally confirmed to be arriving late this year back in October.

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 Homo Aqaua, a re-branded version of the Sea Devils. The Sea Devils are 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 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. Some of their new characters have been announced, while others are still unknown.

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.

The full cast for the series is as follows:

• Russell Tovey as Barclay Pierre-Dupont
• Gugu Mbatha-Raw as Salt
• Jemma Redgrave as Kate Lethbridge-Stewart
• Alexander Devrient as Colonel Christofer Ibrahim
• Ruth Madeley as Shirley Anne Bingham
• Colin McFarlane as General Austin Pierce
• Adrian Lukis as Jonathan Hynes
• Vincent Franklin as Harry Shaw
• Francesca Corney as Hana Chakri
• Mei Mac as Min Tso
• Waleed Hammad as Tariq Hashim
• Hannah Donaldson as Louise Mackie
• Ann Akinjirin as Barbara Pierre-Dupont

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

There is! A full-length trailer is available to watch here.

The War Between the Land and the Sea will air on BBC One on BBC iPlayer, starting at 8:30pm on Sunday 7th December.

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