Psychiatrist Robin Cameron seems on the verge of success with an experimental program that uses a magnetic helmet to trigger, then modify, old angers that cause criminal behavior. She has been working with a promising candidate for behavior modification, an atypical serial killer named Justin Gray. His murders of high school girls involved mixed motivation—he didn't torture them or sexually molest them, and he has to drink to deal with death. Another very reluctant subject of her experimental treatment is LAPD Sergeant Alan Brand, who unwittingly admits to a cold‑blooded killing while under Robin’s care. When Gray escapes and Robin’s teenage daughter, Megan, is kidnapped, Robin does not know whom to accuse—or whether there is something even darker, nastier, and more complicated afoot. The story takes place over a period of only two days, and the suspense does not let up until the last page.