Charming his daughter with the story of how a starfish can regrow its limbs, children's writer Tom Ray (Tom Riley) has no idea of how bitterly ironic that tale will become. When he falls ill with what is assumed to be food poisoning, Tom's wife Nicola (Joanne Froggatt) is convinced that he will be back on his feet after a day in bed and a bottle of Lucozade. However, Tom is belatedly diagnosed with multiple organ failure and sepsis. His only chance of survival lies in the amputation of his lower arms, his legs and part of his face.

Starfish is a gruelling dramatisation of true events that is so conscientiously constructed and unflinching that it almost feels like intruding on a private tragedy. Tom's journey towards a very different life is relentlessly grim, as he is confronted by all the things he can no longer do and the person he will never be again.

The film tilts the balance slightly in favour of Nicola's perspective, as she struggles to cope with two children, care for the man she loves and raise the funds to buy the prosthetics that could make Tom's life slightly easier. Froggatt, also a producer, seems to spend the entire film bathed in tears or tortured by guilt.

The use of sepia-coloured flashbacks to reflect Tom's unhappy childhood almost tips the film towards a form of 'misery memoir' wallowing but director Bill Clark seems determined not to sugar-coat the reality of what Tom has experienced. A rare moment of triumph against adversity provides a climax that is all the more deeply felt because it has been so hard won. Starfish is commendably restrained, thoughtful and well-acted but that doesn't stop it being a tough film to endure.

Selected release from Fri 28 Oct.