CRITICAL MASS, by Sara Paretsky. G.P. Putnam's Sons, 465 pp. $26.95.
When Sara Paretsky first introduced V.I. Warshawski in "Indemnity Only" (1982), she was praised for having created the first credible female private investigator in American crime fiction. Warshawski was physically tough but no bully, courageous yet cautious, plain-spoken, self-doubting.
Thirty-one years and 15 novels later, Warshawski is still instantly recognizable, typically in motion. "After four miles, I was moving in an easy rhythm that made me want to keep going all the way to the Indiana border," she reports of a morning run in Paretsky's latest. "It was hard to turn around and face a day in a chair, but I was one of those people who keep their feet on the ground, their shoulder to the wheel, their nose to the grindstone. What a boring person I must be."
We smile, of course, knowing that she has already stumbled into her latest labyrinthine adventure.
"Critical Mass" starts with a frantic phone call to the office of Warshawski's old friend, Dr. Lotty Herschel. A patient, Judy Binder, has left a message saying that someone is trying to kill her. Judy begs for help and then vanishes, prompting Lotty, who grew up with Judy's mother in Vienna, to ask Warshawski to track her down.
In the course of her investigation, Warshawski finds a photograph that soon draws her into a deeper mystery. In the picture, three women and five men, in 1930s clothing, pose solemnly "around a large metal egg balanced on a giant tripod." The pod, Warshawski learns, is a proton accelerator, and the people are scientists at the Radiation Research Institute in Vienna. One of them is Martina Saginor, grandmother of the missing Judy Binder. In 1941, Martina, a Jewish scientist, was sent to work in a German facility dedicated to the construction of an atomic bomb -- and there's an ominous connection to a present-day defense contractor. Warshawski knows that she has waded into deep waters.
Paretsky's dense, gratifyingly brief scientific explanations link the betrayal, theft and murder at the novel's core. The links between characters, past and present, are less crisp. It is easy to lose track of the connections between relatives, let alone physicists. Yet the tension is sustained and deftly heightened by brief flashbacks to a wartime and postwar world of shifting loyalties and dangers. "I have been in Nazi camps and Communist camps," Martina attests, "and one is not different from the other." Warshawski, for her part, must confront not only killers but also crooked federal agents. Which she does, as always, without breaking her stride.