In second-rate novels about psychosexual homicidal maniacs, we've come to expect a villain whose mad behavior is unconvincingly explained in oversimplified pop-psychiatric terms. This high-strung story, however, has two such loonies to put up with: handsome, icy Everett Madison, who's on trial for shooting his wife and then cutting off her hand with a carving knife; and Martha Sullivan--wife, mother, legal secretary--who takes one look at Everett in the courtroom, has an orgasm (""She felt her clitoris begin to swell""), and from that moment on insanely sacrifices everything to serve and protect poor, innocent Everett. She visits him in prison; she buys him expensive presents; she neglects husband, child, her new psychiatrist, and her job; and, when Everett is convicted and sexually abused by prison-mates, she's prepared to do anything to get money to pay for legal help--she'll even provide sexual services for an aged, bed-ridden millionairess. And when Everett is released on bail awaiting a new trial (a technicality), a last-minute rescue will be required to save cuckoo Martha from the carving knife. Apparently aware of how farfetched this tale seems, first-novelist Davidson refers to actual psychiatric studies and to a real-life case of passion-for-a-criminal-stranger involving actress Sue Lyon. And indeed, a first-class psychological novelist--like Millar or Highsmith--might find some dark pathos in this phenomenon. Here, however, it's just lurid melodrama, unpersuasively reasoned and unstylishly told.