In America it tends to be known as Sudden Infant Death Syndrome (SIDS), while over here it's referred to a little more grimly prosaically as cot death.

It's the unexplained death of a child shortly after birth - and it's one of the leading causes of death in babies despite extensive medical research.

Director Forster's second feature (he went on to make the Oscar-winning Monster's Ball) takes the tragic condition and analyses how it shatters the warm bubble of domestic security.

Pregnant Angie (Mitchell) and husband Russ (Louis) live in a stereotypically American world of lawn sprinklers, clapboard houses and four-wheel drive cars.

Everything is going according to plan when Angie gives birth to a little boy. She's surrounded by loving friends, attentive doctors and an adoring husband... and then the baby dies.

There's no explanation. His heart just stopped beating. The best thing to do, their doctor tells them, is to bury the child and get on with their lives. Of course, it's not that easy. Unsure of how to deal with the situation, Angie's close circle of friends - all pregnant or already mothers - melt away almost overnight.

Russ proves ineffectual while his wife launches into extreme baby-mania, wandering aimlessly through children's clothes shops and even bribing her way into a storage centre to see her dead son's toys.

Shot on digital video, the look is similar to that of a family holiday filmed on garish Super 8, which lends it a day-glo reality that wouldn't have worked on conventional film.

The performances are uniformly excellent, with Mitchell particularly impressive as the grieving mother who simply cannot come to terms with the inexplicable.

It's not comfortable to watch and you wouldn't like to imagine yourself in the position of Angie's friends, desperate not to offend yet delaying any sense of closure she might achieve through their neglect.

So, not an easy movie but a salutory lesson in showing how ill-equipped were are in coming to terms with grief and also a sensitive handling of a difficult subject.

Tim Evans