Maj Sjöwall, Per Wahlöö: The Laughing Policeman (Martin Beck #4)
Celui-là (Le policier qui rit) je ne l'ai pas trouvé chez Barone, alors je l'ai lu en anglais sur ma liseuse...
Plot
A gunman shoots the passengers of a public transport bus with a sub-machine gun; he kills eight people (including Detective Åke Stenström), and wounds one. Detective Beck and his team suspect the mass-murder is to disguise the murder of Detective Stenström, who was spending his free time investigating the sixteen-year-old murder of a Portuguese prostitute. Before that we see the technicality of the story, where Beck tries and removes all the cover from the murder at the bus.