Líba has only one birthday wish every year. She insists that the whole family come together for her celebration, which they all always do. That is, until this year's birthday. Her son Petr has other plans for this year, so he pretends to be sick in front of the family. This year, for the first time, he wants to spend his birthday with his friend Karl, who has a birthday on the same day. And Karel is Peter's long-hidden secret for the rest of the family. However, Líba is not going to give up her celebration so easily. She decides to surprise Peter and move in with the whole family. An unexpected visit forces Peter to quickly improvise. In front of your family, turning your friend Karel into a colleague from work and his sister Veronika into your girlfriend is basically a piece of cake. But Petr doesn't know yet that this is just the beginning and today will be one big rollercoaster ride.