Cross raids a home connected to Emir's murder. The suspect escapes, but leaves behind a piece of evidence so unique, it limits the list of suspects to an elite D.C. few.

With Cross hot on his heels, Ed Ramsey sets up a new locale to perform his kills, as the Cross family continues to be tormented by a mysterious someone connected to Deirdre Nolan.

A fresh lead sends Cross to Philly with his son Damon. Along the way, father and son reconnect through the shared grief over Maria's death.