Black Lightning is recruited to rally against The 100 gang. Anissa investigates the new drug hitting the streets. Meanwhile, familiar faces begin to reappear.

Rebecca and Sam try to save Chester’s Mill residents as temperatures plunge; Barbie puts his life at risk to help Julia after a terrible accident.

Big Jim finally learns what happened to his wife, Pauline; Chester’s Mill faces a new threat — climate change.

Barbie turns to his father for help contacting Julia but realizes that he may not be trustworthy; Big Jim declares himself sheriff of Chester’s Mill.