From the back:
A series of unspeakable crimes are being committed which are so depraved and twisted that even veteran city cops can't look at them. Each murder comes with a name. Somerset doesn't want this case. The city's best homicide cop, he's just one week away from retiring; a week he planned to spend training his replacement David Mills, a real pain-in-the-butt go-getter. But by the second murder, Somerset knows there's a madman out there, and only he can stop him. Somerset figures the way to catch this psycho is to get inside his mind. Mills' way is to blow his head off. They're two mismatched partners combing their violent city for a cunning, macabre, and utterly ruthless killer. And they better catch him fast, because this dark angel is promising to avenge all seven deadly sins and the last one will be the most shocking of all.

Book based on the screenplay.

On route to Florida.