Like Jonathan Valin (below), Greenleaf has come up with a fine narrator in the hard-boiled mode--sardonic lawyer-turned-shamus John Marshall Tanner (Grave Error, 1979)--but has trouble keeping him occupied, plot-wise. Here Tanner has two cases--destined, of course, to link up. First, a San Francisco tycoon hires him to find a long-missing son, a 1960s Berkeley type still wanted by the cops for activist violence. Then, when the tycoon says that the son has in fact shown up, Tanner shifts to case #2: the disappearance of a top investigative reporter. And then it turns out that the tycoon was lying: his son really has been kidnapped, and the two cases now blend, with both trails leading to a radical group's hideout. Somewhat contrived stuff--with worse to come: Tanner also exposes the cause of the tycoon's cancer. . . which involves a ludicrous psycho with wack-o motives. Still, though the plotting is wild-eyed, the action is lively. And Tanner has lots of opportunity to meet a seamily colorful supporting cast, engage in cool dialogues, and dispense shamus-esque imagery (""The cleft in his chin could have lodged a tribe of Hopis""). Disappointingly hoked-up, then, but reasonably entertaining.