Thirty Cases of Major Zeman (Třicet případů majora Zemana) is a Czechoslovak action-drama television show intended as a political propaganda to support the official image and attitude of the Communist Party of Czechoslovakia.

The series follows the life of police investigator Jan Zeman during his career from 1945 to 1973.

Young Jan Zeman is returning from a Nazi concentration camp.

On the train he meets his friend Václav Kalina, who tells him about his plan to join the police force once he gets home.

He reveals a conspiracy and informs Václav Kalina at Brno police headquarters; eventually, the murderers are captured.