Nighttime at the tram depot. A closed tram car, from which a young businessman who fell asleep on the tram finds himself waking up. However, he is not alone...

Ta-ram, ta-ram

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.