A 40-ish man on a London-bound train breaks down in tears, having suddenly lost all memory of who he is and where he's going; no hint of his identity can be found in his pockets, on his clothes. So, calling himself ""John Buck,"" the amnesia victim (whose wallet is full of money, though nothing else) checks into a Paddington hotel and wanders the streets--occasionally hearing instructions from an inner voice (""his secret friend, the other John""), occasionally remembering glimmers of a terrifying childhood. Meanwhile, alternating chapters focus on Helen, youngish wife of the amnesia-stricken John. She is anxiously awaiting his return from London, where he has supposedly gone to show a book publisher his beautiful, obsessive drawings of wildflowers. John has been acting oddly since losing his job as an advertising art director. But there are other, more fundamental problems between the two: the fact (a well-kept secret) that John met Helen when she was working at an ""escort agency""; the fact that John has a basic aversion to sex. So, while waiting for John to come home, Helen desperately shares her secrets, first with friend Angela (a sexy, swinging single), then with John's friend Martin, a lecherous married man. When John (also his real name) does arrive, himself again after his adventures (which also include a nightmarish mental-ward interlude), he finds a new, healthier marriage beginning. . .or does he? There's an ambiguous double-ending here suggesting that parts of the story may have been fantasy, that Helen may be even more psychotic than John, that time frames may have been juggled. Potter, best known for his teleplay/screenplay Pennies from Heaven, maintains a creepy, stark sort of suspense most of the way through this oblique, double-angled psycho-study: the flashbacks to John and Helen's initial encounters are particularly unsettling. But the clinical explanations for the crazed behavior are unconvincing. And the abrupt, confusing final chapters leave this a striking, bleakly intense, yet only half-satisfying exercise in abnormal psychology, slightly reminiscent of Alan Saperstein's Mom Kills Kids and Self(1979).