A steamy Glasgow of the early 1950s: Joe, a rootless young drifter, finds work on a barge owned by the down-to-earth Les and his enigmatic wife Ella. One afternoon Joe and Les happen upon the corpse of a young woman floating in the water. Accident? Suicide? Murder? As the police investigate the case and a suspect is arrested, it becomes evident that Joe knows more about the drowned woman than he is letting on. Meanwhile, against the backdrop of the investigation, Joe and Ella embark on a passionate affair.