Major James Prentis is a British spy of World War II and war hero who goes under the code name of "Shuttlecock". Alienated from his family and children, he ends up in a mental institution in Lisbon, Portugal.
A young Russian officer rescued from being executed by NKVD officers for cowardice arrives at Stalingrad, where he is assigned to the sniper unit. As Russian sniper threat arises, the German Olympic champion is called to destroy them.