Twelve-year-old Thor lived a completely ordinary life. Until one night I made my way with friends to the “Palace” - the most luxurious and famous hotel in the city. The guys wanted to swim in the pool and take a couple of photos, but they ran away in fear when they realized that an unfamiliar girl was looking at them from behind the glass door. In the morning it became known that valuable works of art had been stolen from the “Palace” and the police were looking for witnesses and the perpetrators... Thor knows for sure that he and his friends had nothing to do with it. But the mysterious stranger can’t get out of his head. This girl does not look like an ordinary hotel guest, nor does she look like a painting thief. Who is she? And what really happens in the “Palace”? Thor is ready to take risks and try to unravel these mysteries...