The Dark Formula

Dr Theo Cray is famous for using mathematical methods to track down serial killers. But then he is exposed to a pathogen that affects brain activity, and the knowledge that he has a virus in his body that could turn him into a killer destroys his reputation and his investigation, and he begins to doubt his own sanity. To save innocent lives and himself, Cray pursues every new lead in the case of the deranged nurse, even as he slowly loses touch with reality. But if he is to catch the chameleon killer, he must face his own dark side, for only in the dangerous shadows will he find what he is trying to hunt. And for Cray, the expedition, based not on calculations but only on intuition, is the most terrifying undertaking of his life...