The War Between the Land and the Sea cast and character guide: Who plays whom in the latest British sci-fi miniseries?

The War Between the Land and the Sea is a new British sci-fi miniseries that brings UNIT back into a global emergency. The show builds a tense story about first contact and rising danger from the oceans.

The War Between the Land and the Sea uses both returning heroes and new figures to show how close the world comes to collapse.

The threat returns in the form of the Sea Devils, now known as the Homo Aqua, and their presence pushes UNIT into rapid action.

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The War Between the Land and the Sea cast and character guide

Russell Tovey as Barclay Pierre-Dupont

Russell Tovey plays Barclay Pierre-Dupont. Barclay works at a low rank in UNIT and begins with simple tasks. His life shifts when he becomes the ambassador in charge of communicating with the Homo Aqua. Tovey built a wide career with shows like Being Human and Years and Years. He once played Alonso Frame in a Doctor Who special. Barclay stands at the centre of the series because he tries to calm a conflict no one fully understands.

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Jemma Redgrave as Kate Lethbridge-Stewart

Jemma Redgrave returns as Kate Lethbridge-Stewart. Kate leads UNIT with a steady hand and carries the legacy of her father, the Brigadier. She has guided the group since 2012. Her role gains weight as the threat from the ocean grows.

Kate makes hard calls because peace depends on her decisions. Her presence links the series to earlier Doctor Who stories and helps The War Between the Land and the Sea feel rooted in history.

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Ruth Madeley as Shirley Ann Bingham

Ruth Madeley plays Shirley Ann Bingham. Shirley studies the biology of the Homo Aqua and helps UNIT understand the motives behind the rising species. She first appeared in Doctor Who in 2023. Her findings shape the early strategy that guides the team through the events.

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Alexander Devrient as Colonel Christopher Ibrahim

Alexander Devrient plays Colonel Christopher Ibrahim. Ibrahim works as a key soldier inside UNIT. He helps Kate manage the bases and keep the team steady as panic grows across the coast. His past work includes The Danish Girl and Ted Lasso.

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Colin McFarlane as General Austin Pierce

Colin McFarlane plays General Austin Pierce. Pierce serves in the US Army and works with UNIT as the scale of the threat becomes clear. McFarlane first played this officer in Torchwood: Children of Earth.

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Gugu Mbatha-Raw as Salt

Gugu Mbatha-Raw plays Salt. She speaks for the Homo Aqua and holds direct talks with UNIT at a summit near the Thames. Her calm tone masks sharp anger over the damage to the seas.

Salt becomes a key figure because she forces the humans to face hard truths. Her scenes drive the conflict and bring force to the ending shaped by the cast.

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The War Between the Land and the Sea will air on BBC One and BBC iPlayer on December 7, 2025. The miniseries adds a strong chapter to the Doctor Who universe and shows how one crisis can test every bond between land and sea.