The famous violinist Dorothy Lambert arrives in Bulgaria. She is accompanied by her manager Ted Smiles. The Bulgarian Intelligence Service receives an encrypted message that an agent codenamed Dolly will attempt to contact the chief of residence of a foreign intelligence agency in Bulgaria.

The film is based on the conflict between the Monarch of Bulgaria -Tsar Boris III and general Vladimir Zaimov during the Second World War and discusses different understandings about heroism and self-sacrifice.