The survivors make a stop in Philadelphia they live to regret. Cassandra's old group wants her back, but she left because they're psychopaths.
Addy and Mack are tasked with locating a radio to contact Citizen Z in the Arctic. It isn't long before Addy is captured by Tobias' men and taken to their camp.
Tobias, the father figure of the group, has completely lost it. Cassandra explains he went insane during Black Summer, when his wife became ill.
He states proudly "in time's like these it's eat or be eaten." That's right, Cassandra and her former "family" are crazy cannibals.
Meanwhile, Addy seems to have been accepted into the "family." She soon wanders into a cavern and discovers live human beings with missing body parts.
Garnett arrives at the camp demanding Addy be released otherwise he'll kill them all. Tobias suggests a trade... Addy for his Sunshine. Cassandra agrees to the trade and Addy is set free.
The guys don't give a second thought to leaving Cassandra behind, but the ladies decide to rescue their new friend.
Citizen Z uses an AM frequency allowing our heroes to blast music causing the Z's to follow their truck. The plan works brilliantly!
Eventually, Garnett smashes through the gates, zombies in tow. They overrun the camp and Tobias seeks shelter in that creepy cavern Addy found. The villain gets a taste of his own medicine when his victims begin to feed on him.
Both Addy and Cassandra are saved, all in a day's work for our post-apocalyptic heroes.