In 1974, Jeffrey Dahmer is a high school freshman living in Bath, Ohio, with his parents, Lionel and Joyce, and his little brother, Dave. Jeffrey develops an obsession with a male jogger that he sees every day from his school bus. For a hobby, Jeffrey collects dead animals that he dissolves to the bones using chemicals provided by his father, who is a chemist. This hobby is initiated by his obsessive interest in how animals are "fitted together".