Jack is a witty teenager surviving the monster apocalypse in a well-fortified treehouse. He relies heavily on pop culture to make sense of the ruined world and fights off monsters with a broken baseball bat. Having grown up in foster care, he views his fellow survivors as his only family and privately fears losing them when they discover a working radio.

Quint is Jack's highly intelligent and practical best friend from before the apocalypse. He acts as the group's primary inventor, constantly building and repairing gadgets to keep them safe. He focuses his mechanical skills on fixing the broken radio they find at the fire station, unaware of Jack's anxieties about contacting other survivors.

June is an athletic and highly capable survivor who often proves to be the fastest member of the group. She retains a strong hope that her parents survived the apocalyptic event. The discovery of the radio deeply affects her, driving her mission to establish contact with the outside world.

Dirk is a large, physically imposing teenager who used to bully Jack and Quint before the world ended. He has since transformed into a loyal ally and skilled craftsman who builds custom vehicles for the team. He enjoys acting out fantasy scenarios and happily participates in the group's elaborate games.

The King Wretch is a massive, bat-winged beast with swirling eyes and gnarled skin that suddenly appears in Wakefield. It emits a strong odor of evil and towers over the other creatures in the town. Instead of simply attacking with physical force, it uses its gaze to put victims into hazy, disorienting dream states.

Ŗeżżőcħ is a powerful, otherworldly entity that brought the monster and zombie apocalypse to Earth. The survivor group previously fought and temporarily defeated this ancient destructor. It remains a looming, dark presence over the world as the kids attempt to build a peaceful life in Wakefield.

Rover is a massive monster-dog who serves as Jack's faithful steed and loyal battle companion. He is fiercely protective of his owner and fearlessly charges into danger to defend the human survivors from hostile creatures.

Biggun is a huge, friendly monster living peacefully in the Town Square community alongside the humans. Because of his massive size, he allows the kids to strap shopping carts to his back to create a safe, mobile transport system for their expeditions.

Bardle is a friendly monster wizard who resides in the Wakefield survivor community. He strikes practical deals with the kids, trading the use of his fold-out couch in exchange for their help designing protective gear.

Skaelka is a friendly monster who lives among the survivors in the local community. She acts as a grounded, protective presence, intervening when Jack falls under the disorienting influence of hostile magic.

The Scrapken is a giant, tentacled monster with a single eye and dozens of teeth living in the local scrapyard. It perfectly camouflages itself as a pile of junk and is highly territorial when disturbed, though it is not inherently evil.