Tatiana and Sergey are a married couple who are going on vacation to Turkey after the New Year with their pet rat. When the vacation is over, they go to the local market to buy souvenirs for friends. There Tatyana meets an old man selling antique keys. The girl buys the key that was chosen by her pet rat. Returning home from Turkey, Tatyana accidentally finds out that this key fits their front door. She inserts it into the keyhole and turns it twice. But behind the door is not a landing, but a real space, where their pet rat escapes. Now the heroes have to go in search of their pet.