Jack Caffery and Flea Marley continue to share the spotlight, with their partnership developing into a sort of Lincoln Rhyme/Amelia Sachs relationship (with more sexual tension and as often as not working at cross-purposes). It picks up six months after the conclusion of Skin, with Flea's team in departmental crosshairs, their bonuses at risk and her leadership in question. She is still covering up the death of Misty Kitson for her brother (Caffery witnessed her disposing of the body, and is keeping his distance), and this backstory is filled in as you go along.The main plot is about child abductiona carjacker wearing a Santa Claus mask who steals the car of a vicar's wife, with her 11 year old daughter in the backseat, from a parking lot. Caffery is called in to investigate and is confident the car was the target and the girl will be returned, until Flea reminds him of two other open cases with similar MO, both with young girls in the cars. Then creepy taunting letters start arriving, presumably from the perpetrator. Caffery consults with the Walking Man, the eccentric homeless billionaire whose daughter was abducted and murdered (with whom Caffery has a special bond because his brother suffered the same fate) who warns him that this one is cleverer than anyone you've ever dealt with."When the car from the carjacking turns up, the mud in its tires is mixed with certain metals that suggest it was at a garage or factory, a needle in a haystack but that Flea remembers a factory site her team had searched that matches the specs perfectly. They find tire tracks and footprints and know they are in the right place, but the carjacker has scored through his footprints with something sharp, outwitting forensics, and has deliberately made many different sets of prints leading in all directions into the woods so they won't know where to search.Flea realizes belatedly that a piece of nylon rope at the site could easily be a mooring rope and returns to find that just outside the area they'd searched was a disused canal. She gets Caffery and her team out to search it, finding barge-mooring spikes that match the footprints' score marks. The canal runs partly through an unstable underground tunnel, which is already partly collapsed and threatens to cave in further when a train passes by. Flea puts herself and her number two man at risk to break through a rockfall searching the tunnel but comes up empty. She and Paul Prody (a detective on Caffery's team) both get reamed out for wasting time and money, and end up bonding at a pub. Coincidentally, Prody was the traffic cop who'd breathalyzed her six months earlier when she pretended to have been driving the car that killed Misty Kitson. Flea confesses to him, finally, that her brother was driving.Another girl goes missing in a carjacking, and is returned a few hours later. No one can figure out why the carjacker knows where the traffic cameras are, but he and the stolen cars are never caught on film. The first girl's baby tooth is slipped into an apple pie made for the distraught parents by a neighbor. The family of the second girl is moved to a safe house, but a taunting note at the new location requires them to be moved again. A tracking device on their car explains how the jacker knew where they wereproblem is, the car was never out of police custody, so it must be someone with police access. Suspicion centers on a handyman who got the job with a stolen identity and murdered a girl when he was a teenager. Prody's office was recently painted and the handwriting of a wet paint" note on his desk matches the carjacker's taunting letters. In disgrace, Prody is sent to break the news to the family of the second girl.A storage unit rented by the handyman for the last 11 years connects to a secret passage that contains the body of the girl he murdered years ago, and Caffery believes it connects to the canal they searched earlier. Meanwhile, Flea, not knowing what Caf
