A seemingly innocent man is abducted by a notorious L.A. serial killer, who forces his victims to switch roles with him so that he can enact his own capture, torture and murder.

Four waves of increasingly deadly attacks have left most of Earth in ruin. Against a backdrop of fear and distrust, Cassie is on the run, desperately trying to save her younger brother. As she prepares for the inevitable and lethal fifth wave, Cassie teams up with a young man who may become her final hope - if she can only trust him.