The 8th Plenum of the PZPR is underway. Passengers waiting for a train learn that their traffic has stopped.

A cheerful story about an old lady trying to correct a past mistake and recover a priceless necklace. The heroine develops a foolproof system to ensure that she wins at the casino. The actions of the aged lady attract the interest of a young gambler. He decides to gain her trust and work out the system.