The killing hour - Lisa Gardner

For three summers, the residents of Atlanta have been gripped by terror when the temperature creeps up to a hundred. For with the relentless heat comes a vicious killer. Each time, he takes two girls. When the first body is discovered, it contains all the clues investigators need to find the second victim, who waits, prey to a slow but certain death. The police are never in time; the bodies always found months later in remote and dangerous places.

As a heatwave of epic proportions descends, the game begins again. Two girls disappear and the clock is ticking. Rookie agent Kimberly Quincy stumbles across the first body in the grounds of the FBI training facility at Quantico. She's been face-to-face with a serial killer before and knows only too well why the killer has chosen Quantico to start the chase. This time he's raising the stakes; he wants the FBI's finest to come out and play . . .