MAJ SJÖWALL and PER WAHLÖÖ. The Laughing Policeman (1968).

One thing that Inspector Martin Beck and the policemen who serve with him on the Stockholm homicide squad rarely do is laugh. The emotions that they express, or that Sjöwall and Wahlöö express for them, generally align with the kind of gloom and dyspepsia that have come to define the Scandinavian soul (for non-Scandinavians, at any rate). The disappointments of married and family life, the unfulfilled promise of the welfare state, the dank and dreary skies that hover perpetually over the Swedish capital—these are the topics that typically preoccupy Beck and his comrades, who therefore come across as a dour and serious lot. The title of this novel, the fourth of the ten books that make up the Beck saga, thus contains a strong element of irony. And right away that irony takes on a dark hue, for The Laughing Policeman essentially begins with a dead policeman. Late on an evening in 1967, when the Stockholm police are focusing most of their energies on an anti–Vietnam War protest being held at the U.S. Embassy, an assailant guns down nine people on the 47 Bus as it nears its terminus in the city’s Vasastan neighborhood. Among the dead is an off-duty cop named Ake Stenstrom. Was his killing a mere byproduct of a senseless mass murder? Or was he the intended target of an assassin?

In the now-classic manner of the modern procedural, the investigation of that crime proceeds by fits and starts, with different investigators pursuing different leads with varying degrees of success and (more often) failure. Over time, usable clues—a hidden sheaf of sexually charged photos, a scrap of memory shared by a surviving bus passenger—do accumulate. Then comes a moment, understated but nonetheless climactic, when readers learn the source of the book’s title. Many weeks have passed since the murder spree, and it’s Christmastime. As a present from his daughter, Beck receives a recording of an old song called “The Laughing Policeman.” It’s actually a gag gift of sorts, but it triggers the stroke of insight that Beck needs to arrange an apparently ragtag set of clues in their proper order.

The resolution of the case carries no great surprise, yet it packs a real punch. In large part, that’s because it arises organically from its milieu. Stockholm is a city of islands, populated by residents who skillfully make islands of themselves, and Sjöwall and Wahlöö excel at depicting particular Stockholmers as they inhabit particular locations within that metropolis. The result is a somber, documentary effect that resembles the feel of mid-century noir film and fiction. Still, the noir scene that these authors evoke is a far cry from the prototypical American version. Life in Sweden might breed despair, but social breakdown is a problem that has limited salience in that well-ordered clime. The authors concede as much when they refer—in a glancing albeit telling way—to the day earlier in 1967 when motorists throughout the country miraculously switched from left-hand to right-hand driving.