A ""passive impulsive"" personality is raggedly defined here as one who ""acquiesces to all impulsive ideas suggested to him""--and such a personality is supposedly Karen Medwin, whose obsessive twists and turns on the way to tragedy are set forth in this first novel: a somewhat clinically skewed tale, but one whose gothic excess is both raw and intense. Karen has spent a childhood and youth in an unlovely Delaware working class town, where ""the most vivid life force she remembered was violence""--neighborhood child abuse and spouse-beating. Only child of an alcoholic father (slid far from his family's affluence) and a Jewish mother (in a perennial rage of ""inverted passion""), Karen is vulnerable to her peers' anti-Semitism and generally lonely. So, as a teenager, she runs helter-skelter with a pack of ""hoods"" and their girls--until she flees entrapment by a violent boyfriend and assumes the protection of a nun-like isolation. Then, willy-nilly, she's attracted to the writings of Marx (Iris observations about how rotten it is to be poor seem right on target); and eventually, through the help of a sympathetic, system-fighting teacher, Karen is accepted at New York University. But once in N.Y. socialism is forgotten in the wake of many lovers (""She could never turn a sweet man down"") and a drug scene with rich boy Eric--kind, sensitive, ""a fine instrument warped."" Then, however, Karen swerves away from Eric's suicidal downswing, magnetized to what she believes is true love with doctor John, her ""living ideal."" Karen and John--who is in turn obsessed with this woman on whom ""everything burns like fire""--will malty. Imperceptively at first and then rapidly, Karen, after the birth of three children, swings in and out of madness: a terror of invasion of the security of home by even a housekeeper; withdrawal from the outside world; a reliance on alcohol; and finally, through sinister junkie Matthew, a return to drugs and promiscuity. At the dose, John, drawn just too deep into Karen's elusive psyche and bewitched into a love marked by over-possessiveness and jealousy, commits suicide to avoid murdering her . . . while wretched Karen prepares to obliterate herself after killing the children. A flawed but forceful debut: Vigfusson reads the Saturday Night Fever of her working-class town with impressive verisimilitude--and although Karen's dark passions are very misty and foggy around the edges, they have a flushed and jagged impact.