In a quiet resort town Haapsalu four kids are spending their summer holidays together. Suddenly they are dragged into events that started in the 15th century in the local bishop's stronghold. The children must solve a difficult mystery of a clock robbery and they have to find a treasure that has been lost for centuries and contains a formula of making gold.

Fleeing from the Russian secret police, a young Estonian fencer is forced to return to his homeland, where he becomes a physical education teacher at a local school. The past however catches up and puts him in front of a difficult choice.