They call themselves the Serendipity Group, a charitable organization that helps victims take revenge on those who've wronged them. But when the group's hit list leaks, the hunters become the hunted—and two innocents are caught in the crossfire. A pair of newlyweds are waylaid in Atlanta after a bad storm disrupts their flight to Paris. They are stuck in a dingy airport hotel room—until a stranger insists the happy couple take his lavish suite. But the man's kindness is a ruse: They are being used as bait, and soon find themselves prisoners of a maniac with a hacksaw—all because of a list of thirteen people marked for execution. Ex-FBI agent Xanadu Marx doesn't know how her name ended up on the list, but she'll be toast if she doesn't take herself off it. Now a civilian on parole after a career-killing mistake, Xanadu Marx supposedly has three days to live, and the question isn't whether she has an enemy gunning for her, it's which one. But when two wide-eyed newlyweds may have become collateral damage, Xana realizes that there are some sins that can't be forgiven.