Based on the novel of the same name by Graham Greene, this is a story of a French advocate Chavel who, while imprisoned by the Germans during the occupation, trades his material possessions to another prisoner in exchange for his life when condemned to the firing squad. At the end of the war, Chavel, posing as one of the other prisoners, returns to his home which is now occupied by Therese, the sister of the prisoner he traded his possessions to, and who bitterly awaits the return of the man who had indirectly caused the death of her brother. His real identity unknown to Therese, Chavel is invited to stay as a caretaker and to identify Chavel should he return to the house. The relationship between Chavel and Therese develops until one night, someone calling himself Chavel turns up at their doorstep.