Gangsters try to steal Uuno Turhapuro's father-in-law's money by infiltrating into the family through Uuno, by pretending he has a long-lost son.
Pekko is jealous when Pipsa is under the spell of the handsome Markku. The children Kalle and Katariina enjoy each other's company. Beauty salon owner Kaisa Kuovi and police officer Reino are preparing for their wedding.
Pipsa has fallen prey to a shady scientist Kalevi. Pekko tries to save her.