The 13th hour - Richard Doetsch

At 9pm on July 28, Nick Quinn is given an extraordinary opportunity, a chance to rewrite history and save his wife Mary's life. At 9pm, Nick is being held in jail, accused of Mary's murder. He saw her bloody corpse; he knows that she is dead. That's when a grey haired gentleman presents him with a talisman that allows him to go back in time, one hour at a time, for a total of twelve hours. With each hour that Nick journeys back in time, he finds more clues to the identity of Mary's real killer, but he also discovers that his actions in the past have unexpected repercussions on the future. All his good intentions of saving Mary's life may in fact lead to a far greater catastrophe than he could have imagined. If he hasn't set things right by the thirteenth hour, all will be lost.
A surprising and utterly original thriller that blends a dash of fantasy with page-turning suspense, The 13th Hour has all the ingredients of a massive international bestseller.