Gift Wrap Killer. Eriksson (Darkwater Bay), #13

Helen Eriksson is drawn back into profiling when an alleged family annihilator murders his wife and children in a suburb of Darkwater Bay before he vanishes without a trace. Before she can even begin to examine the evidence, Jeremy Rhodes, the bitter father of a six-year-old child killed by a monster Helen once interviewed early in her career with the FBI arrives. Since his son's murder, he has become not only an advocate for missing children, but also a celebrity sleuth trying to capture criminals who have evaded justice.
He informs the police that he plans to solve their case first, since he's been investigating four identical cases in different states that have occurred over the past decade. His threat to use his celebrity to hurt Helen's family by exposing her in an even more unfavorable light forces her to agree to work with him. With her old mentor, David Levine, Helen and her new adversarial partner delve into a mystery and expose the horrifying history of a killer who seems to view death as a gift.