In the wake of a devastating terrorist attack on a slow New Orleans ferry, the A.T.F. special agent, Doug Carlin, joins an experimental top-secret government program to find the bomber. Designed to bend the very fabric of time, this state-of-the-art technology enables the user to observe a detailed representation of what happened four days and six hours in the past, tracking the target's every move prior to the attack. However, the man responsible for the deadly explosion is bound to strike again. Can Carlin figure out who he is, when he is always precisely four days behind?—Nick Riganas