Mr. Peabody went from adoption agent to principal to dentist.
At first he thought that Junior was innocent, but found out he was wrong about Junior as he conned Ben and Flo into adopting Junior.
After moving to Mortville, he took a job as a principal. Peabody is mean to his students and only wants to be principal, because he hates children. He is horrified to see Junior again, but calls him a genius, and sends him to the 6th grade.
After becoming a dentist, he gives Junior braces, but all Junior had was a broken tooth and Peabody replaced Junior's x-rays with a horse's. Afterward, Peabody is last seen dangling from his teeth from a ceiling fan with his assistant.