Fans of Doctor Who have a special treat to look forward to over the festive season! Although there won’t be a Christmas special this year (although the Doctor will be back for Christmas 2026), there is a five-part spin-off series coming to BBC1 to keep our appetite sated in the meantime.
But for the men and women of the Unified Intelligence Taskforce – UNIT for short – there’s no time to think about Christmas, as they’re facing a very old threat which has re-emerged from Earth’s oceans…
Who stars in The War Between The Land And The Sea?
Russell Tovey as Barclay Pierre-Dupont
Russell Tovey has already appeared in Doctor Who itself, but in the main show we met him as a different character. In the 2007 Christmas special, Voyage Of The Damned, he played Midshipman Frame, an officer on board the starship Titanic. Also starring in that episode were David Tennant and Kylie Minogue, and Russell admits that ‘the opportunity to play Midshipman Frame changed my life!’
In The War Between The Land And The Sea, Russell plays Barclay Pierre-Dupont, an ordinary man with a loving family. He’s not a politician or a diplomat, but nevertheless, he is chosen to be humanity’s representative in the negotiations. Can he do anything to stop a war that will ravage the planet?
Russell has previously played werewolf George Sands in the fantasy drama Being Human (2008-2012), Steve Marshall in the sitcom Him & Her (2010-2013), and Daniel Lyons in the dystopian BBC thriller Years And Years (2019). He’s also appeared in Gavin & Stacey (200-7-2009, 2024), Sherlock (2012), Silent Witness (2002) and Ashes To Ashes (2008), and won plaudits for playing Brian Paddick in the 2025 real-life drama Suspect: The Shooting Of Jean Charles de Menezes.
Gugu Mbatha-Raw as Salt
Like Russell, Gugu Mbatha-Raw has also appeared in Doctor Who back in 2007. She played Tish Jones, the sister of Martha Jones (Freema Agyeman), who was a companion to David Tennant’s Doctor. Tish appeared in four episodes, but sadly, she never got to venture inside the TARDIS!
In The War Between The Land And The Sea, Gugu plays a very different role. In fact, you may not recognise her at all at first, as she underwent many layers of prosthetic make-up in order to play Salt, one of the mysterious Homo aqua who have emerged from the ocean to challenge humanity.
You might also know Gugu from her role as Judge Ravonna Renslayer in the Marvel Comics Universe series Loki (2021-2023), and for playing Sophie Ellis in the psychological thriller Surface (2022-present). Gugu has also starred in Bonekickers (2008), Undercovers (2010, 2012) Touch (2012), Black Mirror (2016) and The Girl Before (2021).
Jemma Redgrave as Kate Lethbridge-Stewart
You’ll recognise Jemma Redgrave, as she has appeared as Kate in Doctor Who in plenty of episodes since 2012 - most recently turning up alongside Ncuti Gatwa’s incarnation of the Doctor in the 2025 season finale. Kate is the daughter of the legendary Doctor Who character Brigadier Alistair Gordon Lethbridge-Stewart, who was played by Nicholas Courtney between 1968 and 1989, and led UNIT alongside several different versions of the Doctor.
These days, it’s Kate who is in charge of UNIT, and she is desperate to stop war breaking out between human beings and Homo aqua. However, if war is the only answer, she’s confident that humanity will be on the winning side.
Jemma Redgrave is still fondly remembered for her role as Dr Eleanor Bramwell, in the ITV medical drama Bramwell in the Nineties.
More recently, she played Bernie Wolfe in Holby City from 2016 until 2022. She has also appeared in Midsomer Murders (2018), Grantchester (2019-2020) and Silent Witness (2020, 2022-2023).
Ruth Madeley as Shirley Ann Bingham
Ruth reprises her Doctor Who role of Shirley, who she has played since 2023. Shirley is UNIT’s chief scientific advisor, but can she help Kate to find a way to ensure peace?
Ruth has previously played Rosie Lyons in the 2019 Russell T Davies drama Years And Years and Chrissy Doolan in the 2024 BBC thriller Nightsleeper.
You might also have seen her in Cold Feet (2017), The Rook (2019), The Cleaner (2021) and Brassic (2022-2023).
Colin McFarlane as General Austin Pierce
Viewers with long memories may remember this character from a previous Doctor Who spin-off series, Torchwood: Children Of Earth, in 2009. Austin is a General with the US army, and if the negotiations between the humans and Homo aqua don’t go well, he’s ready to apply military force!
Like Russell Tovey, he also had a role in the 2007 Doctor Who Christmas special Voyage Of The Damned – as the voice of the Heavenly Host. He also played Moran in the 2015 Doctor Who two-parter Under The Lake and Before The Flood.
Even if you don’t know Colin McFarlane’s face, you’ll know how he sounds, as he was the voice of The Cube for 12 years in the ITV game show (2009-2021).
But in front of the camera, he is best known for his roles as Commissioner Gillian B Loeb in the movies Batman Begins (2005) and The Dark Knight (2008). On television, he played Ulysses in the historical fantasy series Outlander during its fourth and fifth series (2018-2020). He’s also appeared recently in Death In Paradise (2015), Midsomer Murders (2018), Not Going Out (2022), Piglets (2024) and Death Valley (2025).
What is the plot of The War Between The Land And The Sea?
The story is a sequel to a six-part Doctor Who story from 1972 called The Sea Devils, in which human beings encountered the creatures from the ocean for the first time. Although in that storyline, which starred Jon Pertwee as the third Doctor, the creatures were nicknamed ‘Sea Devils’, they are more properly called Homo aqua, as we discover in this new series.
Over the years, mankind has been using Earth’s oceans as a dumping ground for plastics, oil, sewage and all kinds of other pollution. As the sea is their home, the Homo aqua aren’t happy about it! They demand that human beings remain firmly on the land from now on, and don’t encroach on the sea in any way.
A tense negotiation begins between the two species – specifically, between Salt, the delegate for the Homo aqua, and Barclay, the chosen representative for humanity. However, if terms cannot be agreed, it could lead to all-out war to decide who will control the entire planet Earth…
When is The War Between The Land And The Sea set to air?
The first two episodes will be shown on BBC1 from 8:30pm on Sunday 7 December, immediately after the Strictly Come Dancing results show. Episodes three and four will follow at 8:30pm on Sunday 14 December, with the big finale one week later on Sunday 21 December.
Where can I watch The War Between The Land And The Sea?
If you miss watching the show live (December is a busy month for many of us), it will be available on BBC iPlayer. If you’re outside the UK, it will be available to watch on Disney+ in early 2026.
Tom has been a writer for TV Choice and its sister publication Total TV Guide since 2021. He was previously the longest-serving editor of the official Doctor Who Magazine (from 2007 to 2017), where he won an Eagle Award in 2012, and the ACE award for Circulation Excellence by a monthly magazine (2014).