I was a big fan of the Maj Sjowall/Per Wahlöö Martin Beck novels when they were first translated in the 1970s in the U.S., and at the time my favorite was The Locked Room, the 8th of the 10 books. I had reread all of them a few years ago, but recently had occasion to listen to the audio version of The Locked Room recently and was surprised how funny it is (at least when listened to)--sometimes int he ironic way that all the Martin Beck books are funny, but also in a broad comic way. This is one of the most tendentious books in the series, in terms of its indictment of the Swedish so-called "welfare state" of the time, with the narrator occasionally veering into invective against the injustice and neglect that elsehwere is effectively potrahed in the crimes, victims, and even criminals (sometimes) in the series.
The set-up is straightforward: A woman proceeds toward a bank in Stockholm, robs it, and kills a bystander almost by accident. The reader will not revisit this bank-robber until very late in the novel, though the police will focus on a couple of other bnnk-robbers at length.
Afte rthe robbery, we turn to the return of Martin Beck to active duty, after the senior detective of the national homicide squad had been shot in the previous novel (Man on the Roof, very effectively filmed by famed Swedish director Bo Widerberg in 1976--inientally, The Locked Room was not included in the excellent Swedish series based on the Martin Beck books, only appearing on film in the '90s in the German film Beck: De Gesloten Kamer).
Beck is assigned what everyone thinks is a lost-cause cold case, to give him something to do: A classic locked-rom murder (everyone except Beck thinks it's funny that Beck, who never reads crime fiction, has been assigned such a classic mystery novel premise). At the same time, the rest of his squad is investigating the bank robbery from the novel's first pages, but they pursue the notion that a gang of robbers that they have previously been unable to catch (but whose identities they well know) perpetrated this crime as well. One of the results of their pursuit is the spectacularly failed raid on the gang's hideout, a comic catastrophe that is more Keystone Kops than police procedural.
When the solution to both crimes finally arrives, the criminals don't exactly come to justice, at least not in any conventional manner. But the novel's conclusion is satisfying in several ways: in its ironies, in its endorsemenet of the lives of those at the bottom of Swedish society, and in the private life of the usually doleful Beck. In the end, this is no longer my favorite Beck novel (perhaps The Fire Engine That Disappeared currently holds that title), but is a reminder of the very high standard that this series set for crime fiction in Scandinavia, and indeed everywhere else.