Reviewed - Wah-Wah: Twenty years after landing his breakthrough as an actor in Withnail and I, which was set in 1969, Richard E Grant turns writer and director with the semi-autobiographical Wah-Wah, which opens in 1969, writes Michael Dwyer.

The setting is Swaziland, where Grant was born and reared, and the ensuing drama is seen through the eyes of a boy, Ralph (Zachary Fox), who is 11 years' old when he experiences the eye-opening revelation that his mother (Miranda Richardson) is having an affair with another expat. She walks out on Ralph and his father (Gabriel Byrne), the colonial minister for education, who takes to the bottle and sends the boy to boarding school.

Two years later Ralph (now played by Nicholas Hoult from About a Boy) returns home, where his father has married Ruby (Emily Watson), a feisty American with no time for the stiff formalities of the English. It is Ruby who makes the remark from which Wah-Wah takes it title, when she dismisses their quaint phrases such as "tootle pip" and "hubbly jubbly".

Although Wah-Wah takes place as independence looms for Swaziland, Grant is more preoccupied with observing Ralph, his family and their close-knit white community. This is understandable given that there was so much drama within the boy's own home; anticipating the film that would become Wah-Wah, Ralph re-enacts the volatile behaviour of the adults in his puppet theatre.

Grant treats the adults with compassion, reflecting on the sheer boredom of their lives and how it was relieved through alcohol and adultery, and on their fading sense of purpose and status as the colonial era passes into history. Although it slides into melodrama, there is a palpable warmth about this bittersweet movie, and a keen sense of humour as the expats rehearse a production of Camelot to entertain Princess Margaret.

Being the experienced actor that he is, Grant - who stays behind the camera for the duration - gets the casting precisely right and elicits firmly etched character studies. Byrne is particularly effective as his character oscillates between mood swings, and there are some enjoyably ripe performances from Julie Walters as a twittery but despondent deserted wife, and Celia Imrie, imperious as an inveterate snob.