After Hank Pym entered the Quantum Realm to retrieve his long-lost wife, Janet van Dyne, they both returned with a deadly virus that turned people into the living dead. Meanwhile, the Avengers are overwhelmed by the zombie plague that has afflicted superheroes and supervillains alike. However, a group of desperate survivors holds the key to ending the mighty undead. They then race through a dystopian landscape, risking their lives to save their world.