After surviving a sniper attack on the local college campus, crime lab technician Sophie Barrett comes to believe that it was not a random, senseless act and works to make homicide detective Jonah Macon believe her.

When crime scene investigator Brooke Porter arrives at the home of a murdered woman, the only thing more shocking than the carnage is the evidence that someone escaped the scene. But where is this witness now? A thorough search of the area yields more questions than answers, and before Brooke even packs up her evidence kit, she's made it her goal to find the witness and get them out of harm's way.