Inspector Cadek from the 13th police station should keep an eye on the released safe-cracker nicknamed The Cat. He rightly suspects that Cat will go and pick up his last loot which the police didn't manage to find and that he will want revenge on Karta who helped get him behind bars. At the hospital, Cat's ex-lover Fróny hopelessly falls for doctor Chrudimský and decides to start a new life. She still refuses to help the inspector in his search for The Cat and Karta.
In a country whose people have just been successfully persuaded of their superiority and the justification for military expansion by the fiery speeches of a dictator, the bacillus of a highly destructive form of leprosy has spread. It is called morbus Tshengi, or popularly „white disease“. The only one who has developed an effective cure for it is a physician of the poor named Galén. But he refuses to reveal the secret of his cure as long as the powerful destroy human lives through wars.