Harwood (Articles of Faith) is a restless user of genres, and his latest is an odd bird indeed--some Graham Greene flutters, some Eric Ambler flaps--winging its way from identity crisis into thriller territory and back again. Martin Fisher, aging hippie, answers the sudden summons of his estranged haft-brother Gerald and hurries to a seedy North African town (in a country ruled by ""the Colonel""), hoping for a reconciliation; years before, Martin had failed to come up with a phony alibi for Gerald's law-breaking. But his bureaucrat brother is dead on arrival, a supposed suicide, and penniless Martin is stranded in this ""ass-hole of the Mediterranean,"" trying to prove Gerald was murdered, connecting with the local homosexual scene (not an entirely new area for ambivalent Martin), and being harassed and lured by an odd, secretive batch of colonials and natives involved in--what? A ghastly terrorist scheme, of course, which Martin must abet or abort: Gerald's posthumous revenge. But here at last is a cause for directionless Martin to fight and die for, even if his death, however effective, is accidental and ironic. Too contrived to sustain its emotional quiver and too oblique to sustain optimum suspense, Harwood's excursion is nevertheless consistently intriguing in its polyglot dialogues and its faintly absurd, atmospheric tableaux: a muezzin scampering through a minaret; a drunken funeral at sea; a guru preparing for death; a blind concert pianist practicing, sans piano, in a dormitory-like, third-class hotel. For such glimpses and for an elegantly maintained air of Morocco-bound mystery, low-key readers may be willing to overlook this ferry's rather wayward course.