Sherlock Holmes likes to play violin and expects a great career in music. He gets a place in a spa orchestra, but he is again and again distracted by criminal cases. Therefore he is the only one who does not see that his violin has no future. He solves the criminal mysteries in passing but the final test shows that the famous detective is tone-deaf.
More than twenty years after the Second World War, a mining engineer named Fischer is revealed as a former member of the Gestapo, Karel Kraus. He is sentenced for murder to eight years in prison and now works with other prisoners on the renovation of the Convent of St Agnes of Bohemia in Prague. Then a car with a foreign registration begins to park regularly close to the construction site. Its crew, a man and a woman, contact the construction foreman, who probably would not reject a bribe offer to perform some service. The prisoner Bicík is appointed to work with Kraus; Bicík gives him a message from Kraus' brother Bert, who lives abroad, that he wants to help him escape.
The kids were smoking secretly in a barn, set fire and fled. Feeling that the investigation closely, "sits on his tail" and soon will be declared to her parents, the protagonist escapes from home. The charred ruins of the barn, he meets a young man who is also why some carefully avoids meeting people, and tied him. According to the book Hoffmann Ota (Ota Hofman).
Czechoslovak counter-espionage intercepts a coded message from the West German secret service ordering death for an unknown person on Czech territory.
