Expectant followers of Hollander detective Van der Valk should prepare for the worst, the very worst, which happens with shattering finality at midpoint. In Part I Van der Valk, that most nicely proportioned of sleuthing intelligences, investigates some rum minutiae and personnel in a small jewelry/ antique shop. Unfortunately the quarry turns out to be not only perverse, but a killer. . . . If you have the heart for it, you might push on to Part II, wherein Arlette, a widow of erratic intuition and thin-nerved vulnerability, tracks down the assassin with the help of clumsy but warmly supportive friends. Elegant as always, but still the most grievous tragedy since Holmes plunged over the falls.