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 needed to find the second victim - but the clock is ticking...

As an epic heatwave descends, rookie agent Kimberly Quincy stumbles across a body. She's been face-to-face with a serial killer before and knows only too well why this one has started the game again. He's raising the stakes; he wants the FBI's finest to come out and play...