The War Between the Land and the Sea is a British science fiction television miniseries created by Russell T Davies for BBC One and Disney+ as part of the Doctor Who franchise. Starring Russell Tovey, Gugu Mbatha-Raw, Jemma Redgrave and Colin McFarlane, the series features UNIT in their attempt to prevent a global war caused by the return of the Sea Devils, now called "Homo Aqua". The War Between the Land and the Sea was filmed from August to December 2024. It consists of five episodes and premiered on BBC One on 7 December 2025, and is scheduled to premiere on Disney+ in 2026. == Premise == UNIT must take action to prevent a global war once an ancient species, the Homo aqua, comes out from the sea, revealing itself to humanity. == Cast == Russell Tovey as Barclay Pierre-Dupont, a low-level member of UNIT, a transportation arranger, who is unexpectedly appointed as Ambassador by Salt. Gugu Mbatha-Raw as Salt, the Ambassador of the Sea Devils Jemma Redgrave as Kate Lethbridge-Stewart, the commander-in-chief of UNIT Colin McFarlane as General Austin Pierce, a high-ranking American UNIT officer Alexander Devrient as Colonel Christofer Ibrahim, a senior UNIT officer, part of Kate's personal staff Ruth Madeley as Shirley Anne Bingham, UNIT's fifty-sixth scientific advisor, part of Kate's personal staff Adrian Lukis as Jonathan Hynes, a politician initially appointed as humanity's ambassador Vincent Franklin as Harry Shaw, the Prime Minister of the United Kingdom Francesca Corney as Sergeant Hana Chakri, a UNIT soldier assigned to protect Barclay Mei Mac as Min Tso Waleed Hammad as Colonel Tariq Hashim, a UNIT field officer Hannah Donaldson as Captain Louise Mackie, a UNIT company officer Ann Akinjirin as Barbara Pierre-Dupont, Barclay's estranged spouse == Episodes == == Production == === Development === In July 2024, Deadline Hollywood reported a new Doctor Who spin-off titled The War Between the Land and the Sea was set to begin filming in September. Russell T Davies confirmed later that month at San Diego Comic Con that production would begin in August. Produced by Bad Wolf and BBC Studios, Davies is an executive producer along with Pete McTighe, Joel Collins, Julie Gardner, and Jane Tranter. Edoardo Ferretti took on the role of television producer with pre-production underway by July 2024. === Casting === Russell Tovey and Gugu Mbatha-Raw lead the series with Jemma Redgrave and Alexander Devrient reprising their roles from Doctor Who as Kate Lethbridge-Stewart and Colonel Ibrahim, respectively. Tovey and Mbatha-Raw previously played Alonso Frame and Tish Jones in Doctor Who. Ruth Madeley also returns from Doctor Who, playing Shirley Anne Bingham. Colin McFarlane reprises his role as General Austin Pierce, a character first introduced and last seen fifteen years prior in the third series of Torchwood, another Doctor Who spin-off. Adrian Lukis, Patrick Baladi, Vincent Franklin, Francesca Corney and Mei Mac were announced as additional cast members in October 2024. === Writing === The five-part series was written by Davies and Pete McTighe. Davies is the current showrunner of Doctor Who while McTighe also previously wrote for the parent series. The two split writing duties across the programme, with Davies writing the premiere and finale episodes, McTighe writing the second and third episodes, and the two co-writing episode four together. The first read-through for all five episodes occurred on 19 August 2024. The series sees the return of the Sea Devils. === Filming === Some filming took place internationally, including on Mallorca. All episodes were produced in one block, compared to the two to three blocks that would usually be used for five episodes. Location shooting began on 29 August 2024 in Barry and Atlantic Wharf, both in south Wales. Filming continued into September in various locations across Wales, including at the Welsh Government Building, City Arms pub, Hodge House, and Merthyr Mawr. In October, the series was spotted filming at Cardiff City Hall and National Museum Cardiff. November filming occurred at Town Bridge in Newport, Wales. Filming concluded on 10 December 2024. === Music === On 30 May 2025, it was announced that Lorne Balfe had been hired as the show's composer. A soundtrack album of Lorne Balfe's score will be released digitally 5 December 2025. The first track from the album, "Barclay's Theme", was released as a digital single 28 November 2025 and a cover of "'Heroes'" by Alison Goldfrapp and Balfe will also be released as a single 12 December 2025. A physical release of the album will launch in 2026. == Release == === Broadcast === The series premiered on BBC One and BBC iPlayer in the United Kingdom on 7 December 2025, and will stream on Disney+ internationally in 2026. === Critical reception === Ed Power of The Independent criticised the inclusion of UNIT as a primary presence the show, saying that "it's always been a rule of thumb that the more UNIT in an episode, the more boring the results". Power remarked that this was the case for The War Between the Land and the Sea and awarded 2 out of 5 stars. Writing for The Guardian, Lucy Mangan gave 3 out of 5, feeling that the spin-off was "an opportunity wasted", comparing it in an inferior light to Russell T Davies' previous show, Years and Years. Several outlets praised the performance of returning actress Jemma Redgrave, including Radio Times, SciFi Pulse and The London Standard. Isobel Lewis, writing for The i Paper, compared the show to Torchwood, highlighting the use of profanity. Lewis praised Davies' "willingness" to "not simply feed fans the same stories over and over", noting how the finales featuring Ncuti Gatwa's Fifteenth Doctor often "struggled to stick the landing". == References == == External links == The War Between the Land and the Sea at IMDb