Host and retired detective Lt. Chris McMullin gives insights on crimes that took place in a region steeped in rich history and vibrant culture that is known for tenacity and grit. Archival footage, exclusive first-person interviews with former and current Philadelphia area detectives, and cinematic recreations provide an insider's view into the heartrending cases Philly's finest diligently worked to solve. The series delves into the twists and turns of the most harrowing murders committed in the city known as America's birthplace.

Lesser-known but equally lethal killers are revealed through interviews with police and victims' contacts, showing how these murderers stayed undetected while continuing their deadly sprees.