This heart-wrenching, enraging ­documentary by Andrew Thompson and Lucy Bailey is about the last stand of Michael Campbell, a 75-year-old white Zimbabwean farmer who dared to stand up to the racist bullying of President Robert Mugabe. The ­Mugabe government's "land reform" meant evicting white farmers from their properties, ­using a crescendo of threats and beatings. As his horrendous mismanagement of the country got worse, ­Mugabe cynically encouraged his desperate people to focus their anxieties on the supposed white ­villain as a diversionary tactic. He also, cunningly and repeatedly, ­denounces the quaint ­bogeyman of "British ­colonialism" to keep ­neighbouring African states ­loyally ­silent, to keep world opinion and US opinion off-balance and ­uncertain, and thus to make sure that there is no ­appetite for regime change. When it comes to ethnic cleansing and racial ­injustice, western liberals have traditionally reserved their outrage for the Palestinians, or the Kosovar Albanians, or the Iraqi Kurds – but this ­documentary makes a strong, clear case for recognising the white Zimbabweans as neglected underdogs, and for "white African" to be a respectable concept, like white American and white Australian. Campbell himself is a tough ­customer, who has contested the evictions in a ­tribunal convened by the Southern African Development ­Community in ­Namibia, a sensational attempt to bring the Mugabe government to book in an international legal arena. The ­Zimbabwean regime and its lawyers are shown stalling and, all the while, the invasions and intimidations continue. Campbell is effectively under siege, and despite the notionally happy ending of his legal action, the documentary makes it clear that this is a tragedy for ­Campbell, his family and for the country generally. This film is an ­unmissable portrait of courage under fire.