Roger Livesey brilliantly prtys a British officer, Clive Candy, through the rtials and tribulations of three wars, three loves and a lifelong friendship across enemy line.
During the Boer War, Candy is sent to Berlin to trap a German spy. there he befriends a German Officeer, Theo (Anton Walbrook), who marries the girl (Deborah Kerr) Candy is in love with. During the First World War, Candy marries a girl who resembles his lost love and helps Theo-now a Pow-to get repatriated.
Candy comes back in the Second World War as a Brigadier General and once again encounters Theo. On joining a Home Guard exercise, Candy is captured, however, and the two are forced to either aid or betray each other.