Martin Beck, Gunvald Larsson and Alice Levander investigate the mysterious murder of an accountant that was found shot to death at the airport parking. At the same time a reporter receives a package from an anonymous source, with information regarding the embezzling of funds that should have been used for fixing up nuclear reactors. When the reporter contacts Beck, his home gets blown up by a bomb.

Selma, a Czech immigrant on the verge of blindness, struggles to make ends meet for herself and her son, who has inherited the same genetic disorder and will suffer the same fate without an expensive operation. When life gets too difficult, Selma learns to cope through her love of musicals, escaping life's troubles - even if just for a moment - by dreaming up little numbers to the rhythmic beats of her surroundings.