Adolescence and It's a Sin stars confirmed for new Channel 4 action thriller tackling far-right violence

The synopsis for the five-part thriller, which will also star Annes Elwy (Wolf) and Michael Socha (Showtrial), says: "Set amongst the awe-inspiring and unforgiving landscape of Eryri National Park, a close-knit community of climbers is left reeling after a tragic accident on a mountaineering expedition.

"As the group is torn apart by grief, Aaron (Howells) blames himself for the accident and abandons his hometown, to the fury of his sister Seren (Elwy). Coming back after a year abroad, he’s forced to confront his pathological fear of climbing when Seren fails to return from a routine climb.

"Aaron sets off in search of her, facing the mountains for the first time since the tragedy, unaware that an extremist far-right group – the self-proclaimed Justice Crusade, led by the charismatic but unstable former soldier Fairweather (Socha) are also on their own mission in the mountains."

The synopsis continues: "A disparate group of individuals, the Justice Crusade are united by their beliefs and their mutual need for belonging, but as Fairweather reveals his plans, fractures begin to appear, making them even more volatile and dangerous.

"Meanwhile, senior Detective Natasha Evermore (Tremarco) is making her own way to the Welsh mountains. She’s been following Fairweather’s group for some time and is concerned by their recent activity, convinced it could be building to something big.

"As these disparate stories converge on this remote landscape a unique thriller emerges, exploring themes of loss, radicalisation and survival. A wilderness thriller wrapped around an emotional core, Deadpoint is a literal cliffhanger, grounded in the tensions existing in our society today, exploring who we are, who we pretend to be, and what we do when the rope snaps."

Howells, Tremarco, Elwy and Socha are joined in the series by Gary Lewis (A Thousand Blows), John Bradley (3 Body Problem), Sam Keeley (Task), Martin McCann (Hostage), Fflyn Edwards (The Crown) Emily Stott (Foundation) and Ellora Torchia (House of the Dragon).

Filling out the cast are Gwilym Lee (The Great), Michael Jibson (No Return), Crystal Condie (Casualty), Siôn Alun Davies (Steeltown Murders), Oliver Finnegan (Outlander), Rhodri Meilir (In My Skin) and Arthur Hughes (Shardlake).

Gwawr Lloyd, interim head of drama for Channel 4, said in a statement: "Deadpoint is a bold and incredibly tense thriller that places characters and their journeys at the heart of high-stakes action.

"Matt Hartley’s debut script is as gripping as it gets and all set against the breathtaking backdrop of the Eryri mountain range. We’re delighted to be working with Clerkenwell Films and the brilliant cast and crew; this series promises to be as thought-provoking as it is pulse-raising."

Deadpoint will air on Channel 4.

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