The story is set in Tangier when it was an internationally controlled territory separate from Morocco during the years leading towards Morocco regaining its independence.
Sean (Harvey) is held in a castle prison awaiting execution after a bank guard has been killed during a robbery. The robbery may have political implications. Various administrative officials want Sean to say where the money is and the execution is politically important to show that the administration is upholding the law.
Sean, an atheist, refuses to see a priest, Fr O’Brien.
Outside Sean’s girlfriend, Catherine, is drawn into an escape plot and intimacy with Sean’s brother, Dominic. Catherine visits Sean and tells him to see a priest. Dominic arrives at the prison impersonating a priest and with the help of a guard they escape.
Sean and Dominic are reunited with Catherine but they are traced by armed forces. Dominic gets to a car and leads the police away from the others as a decoy. He is chased until he is forced off the road and engulfed in his flaming car. Disfigured and thought to be Sean, he is brought back to prison for execution. Fr O’Brien finds Sean and reveals Dominic is awaiting execution telling Sean that his sacrifice is proof that God exists. Most of the firing squad are disgusted at the execution and fire into the sky but Dominic is executed just before Sean arrives. Sean lifts up his body and declares to the other prisoners that his brother has died to save him.