The pilot opens with Nina, a young mother whose husband left her to fend for their newborn alone as the apocalypse erupts around her. We cut to 17 years later, where we meet a fiery teenager, Io, who is part of a toxic group of humans who hunt for medicine in an abandoned hospital to save their community from a typhoid outbreak. Io and the crew break into the hospital and split up. Io and her teammate find the medicine but get cornered by an infected, bloodthirsty human known as a Feral. Io tosses the medicine to her other teammates, but they leave Io behind to die. When all seems lost, she's saved by a mysterious girl acting…rather odd. Upon reuniting with the rest of the crew, they see the girl burn in the sunlight. She's infected. The girl tells Io that her name is Nina, causing Io to attack her crew members to protect her. The crew subdues the two, taking them their separate ways for punishment. Nina is brought to The Slaughterhouse, where she meets Dr. Weise, a scientist tasked with performing a blood test on her and must complete it in 24 hours. Weise tells Nina that she's a new breed of human with a ravenous thirst for blood and is nearly unstoppable. Io is taken to a makeshift trial, where the crew complains to her dad, Old Timer, that she attacked them to save a Feral, which is against the law in their community. Io shares with her dad that the Feral told her her name is Nina, and she is his long-lost wife. Io is sentenced to death, but Old Timer helps her escape. They team up to infiltrate the Slaughterhouse to release Nina...who has reverted to her ravenous thirst for blood and attacks, leaving off on a cliffhanger.