In Family Matters, Daniel Gottlieb writes, "In many marriages, sex becomes a metaphor for what's going on in the relationship and within each partner. Sometimes sex is a battleground. At other times, it may represent power and control, punishment or a test of wills. And it's even a test of love." The marriage of Max Raphael (Hugh Bonneville) and Stella (Natasha Richardson) has problems. He is busy with his new job as deputy superintendent at a psychiatric hospital in northern England in 1959. He scolds her for not talking to women at the first social gathering of the staff. Apart from her love of their ten-year-old son Charlie (Gus Lewis), there is no joy at all in their perfunctory relationship. She has a rebellious side to her nature which Max finds very irritating. He is constantly trying to rein her in and subdue this aspect of her personality. It irks his snobbish and prudish mother Brenda (Judy Parfitt) as well.
While Stella is trying to please her authoritarian husband by working in the garden, Charlie introduces her to Edgar Stark (Marton Csokas), a patient who is repairing a greenhouse. Although allowed certain privileges, this young man, a former sculptor, suffers from severe personality disorders and attacks of morbid jealousy. Dr. Peter Cleve (Ian McKellen) has been keeping a close eye on him. After dancing together at a patient and staff ball, Stella and Edgar begin a torrid sexual affair which takes place mostly in the greenhouse. This passionate arrangement seems to benefit them both. Of course, it is only a matter of time until they are caught.
Edgar escapes from the psychiatric hospital and sets up a place in London with a friend Nick (Sean Harris). Forced to choose between her son and her lover, Stella joins the fugitive. The dark side of Edgar's personality emerges when he becomes convinced that she is having sex with Nick. After the police close in on Edgar, Stella joins her husband who has taken a new job in Wales. There are further challenges to their marriage and to her.
David Mackenzie directs this psychodrama that is based on a novel by Patrick McGrath. He seems to have a penchant for exploring where compulsive sexuality leads people; it was also a theme in Young Adam, the last film he directed. Natasha Richardson carries the story with an intense and rigorous performance that calls upon her to be both the belle of the ball and an adventurer who is bent on self-destruction. The film is a cautionary tale on what Tibetan Buddhists call the dangers of "licking honey off a razer."
Hugh Bonneville is convincing as her domineering husband, and Ian McKellan turns in a wry performance as Stark's psychiatrist who derives gleeful satisfaction in living through the passions of others.