An American adventurer who has a gambling den in Istanbul, who is suspected to be involved in the kidnapping of a nuclear scientist, but ultimately becomes self on the search for the disappeared and gets a striving for world domination secret organization.

Andras Pulac, a young pianist, refuses to perform a concert in honor of a senior Soviet leader, as a sign of rebellion against the 1956 invasion of Hungary. His refusal, although he does not know it, harms the organizers of a demonstration against the communist cruelty, since his concert had been chosen like slogan. When Pulac finds out, he agrees to give the concert. Andras and Maria Kondor, the daughter of a communist journalist, are in love and decide to get married before the concert. Meanwhile, communist repression in the streets provokes the anger of the Hungarian people and gives rise to a real revolution.