In the royal castle, Prince Matej feels like a prisoner. His father forces him to be engaged to Princess Beatrix, whom he does not love. Matej takes advantage of a chance meeting with the tramp Tomáš, who is his identical double. The boys swap clothes and agree to try out each other's lives for a day. In the morning, Matej is falsely accused of theft and imprisoned. Tomas has to stay in the castle and even though he tries to convince the king that he is not the real prince, no one believes him. Both boys must face a world they have never known, grow up and learn to take responsibility for their decisions. Their reward will be that they both find true love.