HALFLIFE

The author of Pestis 18 (1986) concocts another medical-thriller with just enough authoritatively presented jargon to approach believability. The Manchurian Candidate meets Sybil. Twenty-two years ago, the CIA (or was it a Soviet mote in the CIA?.) experimented on children by infusing the right hemispheres of their brains with a ""construct,"" Jonathan, who is the ideal courier and psychopathic assassin. The experiment was deemed a failure and abandoned. Now, Atlanta is being terrorized by the D-string killer, a maniac who with piano wire garrotes his victims and then carves a name on their corpses--Jonathan, of course. When writer Tim Monahan receives a personal invitation to what is billed as a weeklong study of creative individuals--which will take place in the deserted, gloomy wing of an Atlanta Hospital--he suspects nothing. Like Monahan, who suffers from memory lapses, the other participants in the study have strange psychological lives. One suffers from multiple-personality syndrome. Another is a medium whose novels are dictated by her 200-year-dead control, Paul. Monahan grows suspicious. Is the director of the program working with Atlanta police to discover Jonathan, or is he trying to resurrect the CIA's diabolical plan? Which of the bizarre people in the musty old hospital wing is the killer? Might it be Monahan himself, during his memory lapses? After a slow start when the novel labors overly hard to convince us that the premise is scientifically plausible, it hits a quick enough stride once the characters begin to interact. The story is a touch familiar and the ""surprise"" ending is a bit predictable, but, still, Webb's second is a mildly diverting entertainment.