The Killing Habit

Description for THE KILLING HABIT by Mark Billingham:

THE KILLING HABIT again brings together favorite wild-card detective Tom Thorne and straight-laced DI Nicola Tanner on a pair of lethally high-stakes cases.

While DI Nicola Tanner investigates the deadly spread of a dangerous new drug, Tom Thorne is handed a case that he doesn't take too seriously, until a spate of animal killings points to the work of a serial killer. When the two cases come together in a way that neither could have foreseen, both Thorne and Tanner must risk everything to catch two very different killers.

This is #15 in A Tom Thorne Novel.