Oranges and Sunshine (12A)

Starring: Emily Watson, Hugo Weaving

Jim Loach's docudrama unfolds the true story of a binational scandal. Emily Watson plays Margaret Humphreys, a Nottingham social worker who in 1986 began investigating cases of child migration that stretched back for years: often without their parents' knowledge, children in care had been deported from England to Australia, where the prospect of "oranges and sunshine" was soon exposed for a quite different upbringing in severe – and sometimes abusive – institutions.

Humphreys, shuttling between home and Oz, becomes almost a one-woman crusade in reuniting these sundered families and revealing the long-standing injustice as a Whitehall-approved scheme. These stories of enforced separation could hardly be more upsetting, and Hugo Weaving, as one of the deportees damaged well into adulthood by his experience, gives a hugely affecting performance. Cinematically, though, the film doesn't really work, dependent on undramatic scenes of Watson furrowing her brow over paperwork or facing down objections to her dirt-digging campaign. A promising narrative strand in which a grown-up migrant (nicely played by David Wenham) finally persuades her to visit the remote care home, where he was raised in slave conditions by Christian Brothers, eventually peters out in anticlimax. One suspects Humphreys's book, on which Rona Munro's script is based, would be a harrowing read, but the internal drama of those child migrants is only briefly glimpsed here.