In 1968, Czechoslovakia is on the verge of a revolution, and Polish troops are sent into the country to put down the insurgence. Romek is a Polish soldier who has been having an affair with the wife of his commanding officer. While Romek believes the officer is unaware of the infidelity, he senses that his cover has been blown when he's assigned to roll across the Czech border in a broken-down old tank that barely runs. As Romek and his comrades make their way into Czechoslovakia, they get lost. Things get worse when they crash into a small town tavern, where many of the locals are throwing a party for the local postmaster. The arrival of Romek and his fellow Poles is not welcomed with enthusiasm by the Czechs. But when the soldiers realize their tank is not going anywhere, they convince some of the locals to help them.