Mind kill - Richard La Plante

Bill has retired to Santa Fe, New Mexico and is living with Diane Genero, the first woman he has had a relationship with since the tragic death of his wife and daughter. Josef Tanaka, in Philadelphia, has become involved in the post mortems of five people seemingly unconnected except there is no apparent cause of death. Justin Gabriel, a brilliant postgraduate student of clinical psychology who had also studied diablero (black magic of the Sonoran Indians) and formed a quasi-religious sect, is now in prison serving 20 years. Tanaka discovers that his five bodies had all played a part in his arrest. Fogarty appears to be the next target for revenge, and the means by which Gabriel tries to extract it are far beyond anything that Fogarty or Tanaka have ever encountered.