I can’t really explain the circumstances that led me to read a Swedish police procedural published in 1970, but I’m glad I discovered this gem of a book. It is written in a straightforward style with spare, precise language that propels the story along. The mystery begins with the discovery of a bus on which all of the passengers have been brutally shot. One of the passengers is a police detective who didn’t belong on the bus in the first place. A team of detectives take on the case, and despite the absence of leads, eventually work out the convoluted solution. The resolution may seem like a bit of a stretch, but it’s the getting there that provides all of the enjoyment. I had some difficulty following the plot with all of the unfamiliar Swedish names and the roundabout way the case was solved, which only means that this may be worth rereading someday.