Which boy did not dream in childhood of becoming a famous detective, such as Sherlock Holmes or Hercule Poirot? Kalle Blumkvist, the hero of the story by Swedish writer Astrid Lindgren, did not escape this either. In his quest to catch a criminal in a small provincial town, he unexpectedly finds himself on the trail of a real robber. Kalle has his own team - the Knights of the White Rose, who are ready to come to his aid at any time. But at some point the boy begins to realize that the exciting game is becoming unsafe...