The film is based on a true occurrence in Sweden in 1988. A Finnish couple murdered a young boy and his parents when they prevented the theft of the son's bicycle. The film tries to describe the relationship between the dominant Jari, who calls himself "Il Capitano", and his more mature "soldier" Minna, that develops into mutual dependence.
A film that pushes every stereotype imaginable about Finland, and then some. Indeed, coming in the same year as Finland’s 50th anniversary, the film’s whole premise is about presenting Finland in hilarious fashion to foreigners and perhaps also making fun of some of the myths of Finnish culture for Finns themselves.
Justiina pushes Pekka and Pätkä to take painting lessons after realizing that art can be a way to earn a living. With the help of the yard children, a painting is created that wins first prize at a contemporary art exhibition. In the meantime, the men, along with their assistant Miss Kaihokielo, have been charged with art theft. After the misunderstanding is cleared up, the Puupääs use the art prize money to convert the house's bomb shelter into a children's clubroom.
Pekka Puupää and Pätkä, who return to Helsinki from an unsuccessful variety show tour, are forced into refresher training, where they are trained as frogmen. During the diving exercises, the friends encounter the mermaid Helmi, whom they help into the bathtub at home, to Justiina's shock. The friends, who have become civilians, eventually end up on a plane bound for Suez, being cornered by UN soldiers.