During the German occupation of Greece in World War II, Lt. Carl von Stein is quartered in the house of Prof. Victor Kastriotis. The professor lives with his wife and a niece, Liza, who studies at the Athens Conservatory.
The German officer falls in love with the niece who reciprocates however, she turns down his eventual proposal of marriage. Von Stein cannot understand Liza's behaviour towards him until she confides in him that she is not really the niece of Prof. Kastriotis but a Jewish girl that he has been hiding.
Von Stein is upset by the revelation and betrays Liza to the Gestapo. Afterwards, he volunteers to fight in the Eastern front.
After the war ends, he returns to Greece to find Liza. He discovers that she has died in a concentration camp. Von Stein then goes to Kaisariani, hides behind the targets of the local shooting range and is shot dead by soldiers taking their shooting practice.
- Petros Fyssoun - Lt. Carl von Stein
- Manos Katrakis - Prof. Victor Kastriotis
- Georges Sarri - Mrs. Kastriotis
- Dimitris Myrat - Dr. Heinrich Stockmann
- Elli Fotiou - Liza
- Dimitris Nikolaidis - Police Officer Zakas
Betrayal won three awards at the Film Festival of Thessaloniki:
- Best Male Actor (Petros Fyssoun)
- Photography (Nikos Gardelis)
- Best Film as voted by critics
- Betrayal was inspired by Notis Pergialis
- It was entered by Greece in the 1965 Film Festival of Cannes
- Almost 20% of the film consists of Nazi German film footage