An adventure film about the struggle of the Czechoslovak security authorities against Western agents. In an express train departing from Nuremberg station, a cigarette box with plans and instructions for the destruction of one of the Czechoslovak dams is stuck under the seat. The State Security is informed about the whole operation and tries to catch the foreign agents.

• Studio uměleckého filmu Praha
• Ludmila Vendlová
• Bohuš Záhorský
• Josef Bek
• Jaroslav Marvan
• Zdeňka Baldová
• František Filipovský
• Svatopluk Beneš
• Miroslav Homola