The team heads to the Appalachian Trail in rural Virginia in search of a serial killer operating around it. Meanwhile, Reid is faced with a dilemma involving his mother's health.
Walter learns Cabe's long-hidden secret regarding the Baghdad mission and it threatens to tear Team Scorpion apart. Meanwhile, Ralph puts his life in danger to help the team.
Avery and the team pursue a serial killer who has hacked the website of an online car service in order to use it to locate and murder the service's customers. Meanwhile Daniel is forced to confront a tragic event from his past.moreless
The residents of Jericho have survived the attack on their town but there is a lot more in store for them.