Robert Sawyer has won many awards for his science fiction, which is praised for its blend of high-tech mystery and suspenseful pacing. An experiment has gone terribly wrong. Dr. Peter Hobson has created three electronic simulations of his own personality. One will test life after death; another, immortality. The third one is the control unit. But now all three have escaped from Hobson's computer into the worldwide electronic matrix. And one of them is a killer.