Arnold Z. Ombee, a young zombie, escapes the secret government lab that's developing zombies, and is found by a human couple named Jenny and Bill Kinder. They disguise his appearance, teach him how to act like a human boy, and make him a part of their family along with their son Lester. Lester tries to help Arnold blend in, but Arnold worries he won't be able to keep his identity secret when he starts fifth grade.