This depiction of sex and perfidy in the Roman Catholic church, based on a novel by José María Eça de Queiroz, has become Mexico's biggest ever box office smash thanks in part to a dose of holy condemnation. Its strongest suit is treading the moral grey zone cast by the shadow of power. Free from its orbit, an ordinarily well-meaning, but weak-kneed, jobsworth like budding Father Amaro (García Bernal), who has come for pastoral training to the town of Los Reyes, Aldama, might well stand by his humanity and human nature. He might argue for his reciprocated passion for a local beauty like Amelia (Claudia Talancón), and even share the load of a colleague such as Father Natalio with whose liberation theology he clearly sympathises. But this is Mexico, where the weight of conservative Catholic orthodoxy, complacency, influence and vested interest itself constitutes a temptation to corruption. Away from the fire, though, these hardly seem scandalous revelations; and while the bare bones of the tale are given plenty of flesh, it never takes a persuasive shape. It's a compelling story, but an unexceptional piece of cinema.