A death-defying ordeal in an impossible situation has been the inspiration for many true-life dramas, often to startlingly good effect. There’s a pleasure in watching people act competently and cleverly to help one another, and inspiration to be taken from their example. Sadly, this feature adaptation of director Alex Parkinson’s own 2019 documentary of the same name is so faithful that it undercuts its own drama.

There should be real drama here, too: the 2012 incident that inspired this film is horrific. Chris (Finn Cole), Dave (Simu Liu) and Duncan (Woody Harrelson) are deep-sea divers who specialise in tending and repairing oil pipelines. They spend a month at a time in a pressurised tank to work on the bed of the North Sea, a terrifying prospect even before bad weather and computer failure cause the ship to which they’re tethered to drift, resulting in Chris being left on the...