The key to solving the toughest homicides lies somewhere in the final hours of a victim's life. In each one-hour episode, determined investigators must piece together events during this critical window to reconstruct the timeline, unlock the motive, and ultimately close in on the killer.

Follow determined investigators working the most shocking murder cases as they reconstruct the tragic final hours in the victim's life, in order to find their killer and crack the case.

(CA) A team led by criminologist and former detective Dr. Mike Arntfield uses its advanced skills, which include medical biophysics and private investigating along with 21st-century technology to try to solve longstanding mysteries and give victims' families closure. In each episode, the team goes into the field in search of new leads by talking with family members, dissecting new and old evidence, and re-enacting the crimes in their quest to solve these longstanding mysteries.