Mother Irma turns 65 - which puts her children under stress. Businesswoman Kathrin, single mother Nettchen and student Laurenz actually prefer to avoid each other. But now they decide to invite Irma to their old vacation home by the lake. But the cheerful celebration turns out to be a disaster: Surprise guests such as Laurenz's hot new flame, the family's Danish friend and Irma's old girlfriend, with whom she has fallen out, are annoying. And then the siblings start to reproach each other.