If Joaquin Phoenix really has decided to give up acting, as he claims, American cinema will have lost one of its strongest, most imaginative male leads.

In James Gray’s family drama he plays Leonard, who is bipolar, with a history of acute depression. He is pushed by his anxious Jewish family (Moni Moshonov and Isabella Rossellini are his parents) to take over their dry-cleaning business and marry the girl whose father holds all the financial aces.

The girl (Vinessa Shaw) fancies Leonard rotten and would make him a fine wife. But he falls instead for the emotionally unstable girl next door (Gwyneth Paltrow), who is embroiled in her own hopeless affair with a married man (Elias Koteas) who has no intention of leaving his wife.

Most of Gray’s darkly imagined thrillers have a fractured family at their base so this isn’t entirely new territory. Once again, with the aid of a good cast, he chronicles the middle-class life of New York’s outer boroughs with considerable skill.

Film Trailers by Filmtrailer.com

But it is Phoenix’s depiction of an unstable man split between familial obligations and a desperate need to get out that makes the film. The detail in his performance as he struggles to make sense of his life is magnificent. It’s one of Gray’s quieter, less melodramatic films, but it’s among the best.