FW Murnau’s final, late-silent-era film clangs PC alarm bells with its reference to a group of “half-castes”. Retro-grade imperialism? Condescension? Ah, but Tabu transcends all that. Begun in collaboration with a documentarian, the Nosferatu director’s folk tale of doomed love is a sensual cine-hymn to sexuality’s struggle against patriarchy. Ostensibly heterosexual, its homoerotic undercurrents are clear.