Little Oddemann uses every means available to find Jesus, including his slingshot. The film takes us to Norway in the late '30s, where we meet a series of burlesque and humorous characters, whose antics convince Oddemann that growing up may be a bad idea. Yet Oddemann finds there are certain rewards to being grown-up, such as partying and chasing women, that merit closer examination.

When the charred remains of woman are found, Säpo, the Swedish Security Services, suspect Gunvald Larsson of being mixed up in her murder. The dead woman was wanted internationally and a member of a group of militant eco-activists carrying out attacks around the world. Gunvald sets out on his own to find the woman's murderer, with Säpo on his heels. Martin Beck is ordered to arrest Gunvald and his loyalty to his colleague is now put to the test.