It is moments before dawn, and the river traffic on the Thames begins to ease its way through the fog. The river police find the body of a young girl left by ebb tide. Her body is brought ashore and her possessions examined. Who is she? And what drove her to take her own life? For the young married couple (Judi Dench and Norman Rodway) love brought them together, but now marriage and a child have driven them apart. The young husband would rather stay out than return home to a wife kept awake by a teething baby daughter. Their story is witnessed by their friend (Joe Melia), a bachelor, who is the loneliest of them all in the group. At the same time two young lovers meet outside a nightclub. Desperate to make contact, but afraid of what their involvement could mean, the girl (Ann Lynn) shies from physical contact and the boy (Brian Phelan) cannot cope with his feeling of being trapped by the love she offers.