Heidemarie pays her husband back with her last breath: one of her three children was the result of an affair, she breathes - and dies. Ulrich, a newly retired airline captain and old Casanova, gets the moths. Accompanied by the mocking spirit of his "Heide-Maus" and dog Specki, the Berlin widower jets from Hamburg via Hanover to Kassel to collect samples for a genetic test from his now grown-up offspring. It turns out that the marriages of daughter Bettina and son Christian are also on the rocks. Only his future daughter-in-law Jessica, the bride of Ulrich's flighty son Thomas, is happy about the widower's visit.