Everything we know about Doctor Who spinoff The War Between the Land and the Sea

Thanks to an investment from Disney, the new era of Doctor Who is very exciting. The franchise has a bigger budget to play around with than ever before, and with new installments airing on Disney+, the show is able to reach a much larger audience. Despite a lackluster debut season on Disney+, the House of Mouse and BBC’s collaboration continues to grow with an all-new spinoff series, The War Between the Land and the Sea.

The War Between the Land and the Sea is currently in production. The UNIT-focused spinoff began filming in August 2024. Created by Russell T. Davies and Pete McTighe (A Discovery of Witches, The Pact), the 5-episode spinoff sees Jemma Redgrave, Ruth Madeley, and Colin McFarlane reprise their roles as UNIT's Kate Lehbridge-Stuart, Shirley Anne Bingham, and Torchwood's General Pierce. Previously announced cast members include Russell Tovey, Gugu Mbatha-Raw, and Alexander Devrient.

The series is also directed by Dylan Holmes Williams, who helmed two of the most popular episodes from the latest series: 73 Yards and Dot and Bubble.

What is 'The War Between the Land and the Sea' about?

While plot details for The War Between the Land and the Sea are currently under wraps, we have an outline of what the spinoff will entail. According to a tagline from the BBC, the show will be a full-scale war... and this time, the Doctor is not on Earth to help out. The duty to save humanity falls to UNIT.

"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."

The threat happens to be the Sea Devils -- one of the Doctor's oldest enemies. The Sea Devils first appeared in the Whoniverse way back in 1972. The underwater villains have only appeared once in the modern era of the franchise, in Legend of the Sea Devils (2022). While the episode was not quite the triumphant return everyone hoped for, the upcoming spinoff will aim to give them their due.

Furthermore, during San Diego Comic-Con, Davies explained that the Sea Devils wage war on humanity due to the state that we have left the oceans in. "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 a war on an epic scale."

Russell. T Davies teases 'seven seas of danger' in the spinoff!

Ahead of the show's production, showrunner Russell T. Davies took to Instagram to rhapsodize about the spinoff. He teased high-stakes action, and trouble lurking around every corner. Without the Doctor around, humanity is in one of its most precarious states yet.

"Day One. The war begins. Read-through day for all five episodes of The War Between the Land and the Sea," he wrote. "So much excitement. What a cast! Thrills, deaths, chases, fish, and seven seas of danger. Can’t wait!"

The War Between the Land and the Sea doesn't have a release date yet. These are still early days. You can expect it to premiere sometime in late 2025, or even early 2026. In the meantime, we've got Doctor Who season 2 returning on Christmas Day and into 2025. You can also dive down the Doctor Who archives and check out The Sea Devils (1972), which chronicles their first appearance in the franchise.