It's a steamy, sultry day of a hot Mediterranean summer. Terence, a rich London lawyer, his beautiful wife Cathy, a doctor, and their young daughter Lucy are relaxing on the yacht that is Terence's pride and joy. Suddenly, a storm whips up from nowhere and Terence battles into the night to save the lives of his family. Battered and bruised, they limp into Dubrovnik harbour. Unable to go ashore until daybreak, Cathy tends to her daughter's injuries when a large motor-cruiser pulls up alongside the yacht. Its wounded skipper, the enigmatic Kurt, comes aboard the family's yacht also seeking medical help. As the darkest hours slowly tick by, Terence and Cathy have to listen to Kurt's disturbing story. At sunrise, Terence is a changed man, desperate to cling to his wife and daughter, and accordingly willing to change his life - a life about which, it transpires, he has been somewhat less than candid.