A small Mexican village early in the 20th century. Otilia is a sensual young girl with an ideal body whose face is marred by an enormous mole. As a result, Otilia grows up friendless, except for the companionship of Melquiades, a young man employed by her family. Rich landowner Don Isaac arranges for Otilia's marriage to the local police chief, Isidro. A cruel and venal man, Isidro infects his young wife with a venereal disease that renders her sterile. With the help of Melquiades, Otilia takes a series of lovers, both for pleasure and to spite her husband. However, she falls deeply in love for the first time in her bitter life when the wounded Ruben, an outlaw and assassin with a bounty on his head, appears at her parents' deserted farm. Isidro begins to grow suspicious - he is among those pursuing the valuable outlaw, but refuses to imagine that his wife might be harbouring him - and even Melquiades becomes jealous and resentful of Otilia's new love.