White art about colonialism frequently favors the Heart of Darkness narrative: a white man penetrating the wilds and losing his superficial bond with “civilization.” But in the new film from Jennifer Kent (The Babadook), set in Australia in 1825, “civilization” is merely a handy euphemism for exploitation and genocide. After British soldiers rape her and commit horrific acts against her family, an Irish convict, Clare (Aisling Franciosi), hires an Aboriginal tracker, Billy (Baykali Ganambarr, in his first-ever acting role), to help her hunt down the bastards in the Tasmanian jungle. Clare initially calls Billy “boy,” and Billy is justifiably reluctant to work for a white woman. In this suspenseful, moving, and often hard-to-watch film, their changing relationship is a rare solace amidst scenes of historically accurate barbarity.