One of the factors that intensifies the excitement and tension of an adulterous affair is the danger of being caught. Add to that the fierce, idiosyncratic passion often attributed to artists and make the artist a raving psychopath and you have a pretty heady mix.

So finds the story of Asylum, director David Mackenzie's further foray into shadowy worlds of sexual obsession, violence and madness. Stella (Natasha Richardson) is wearily married to Max (Hugh Bonneville), a psychiatrist, working in a Fifties hospital for the criminally insane. He is overbearing to the point of being monstrous (by modern standards), joking to her about being his "pet patient," whilst expecting her to be a no-brainer wife, who says the right things socially.

In the initial build up, Mackenzie lets us see the smouldering lust in the face of inmate Edgar (Marton Csokas), who's incarcerated for murdering and decapitating his wife in a jealous rage. Just as he did in Young Adam, Mackenzie excels at portraying barely sublimated animal sensuality, which soon bursts across the screen in a way that is both base and beautiful. Stella knows how insane Edgar is, but finds herself gradually drawn into his web, together with her son.

Like an insidious sense of darkness creeping up from the unconscious, visually splendid in dank grey tones, Asylum is an explosion of repressed sexuality that is frightening in its force and surprising in its ending. Richardson is fantastic, as an ignored woman with a desire to be desired that wreaks destruction.

Morbid, unsettling, erotic and deeply disturbing.