Alyosha Seroglazov goes to the sea with his mom, dad, and loyal Kysh, and they find themselves in the center of mysterious events. Alyosha has to solve many riddles: why is their hostess happy when her things go missing? Who carved a confession of love for Crimea on the statue of Hercules? Where did the two most beautiful feathers from the tail of the peacock Pavlik disappear?