James Prothero, forty-three years old and up to his ears in alcohol, is the skipper of a tramp ship due to leave South America for Britain – and he’s sick to death of carting goods back and forth across the world. Then he meets Manuela, a beautiful native girl smuggled on board by one of his crew, and comes to realise that she, too, is a lost soul. Gradually a love affair develops between them, and Prothero becomes dangerously blind to the responsibilities of his position.