Homer and Marge recount the story of their transition from loving their life without kids to being miserable parents.

Mr. Burns goes undercover as "Fred" at the nuclear power plant and becomes friends with Homer and the gang. Burns implements all sorts of amenities to improve his employees' lives, but a jealous Smithers plots to bring the old, bitter Burns back and destroy Fred.

Lisa travels back in time to 1923 and discovers that the Springfield Mini Moose, once key to the town’s ecosystem, were driven to extinction in 1925. Teaming up with young Monty Burns, Lisa works to save the moose, but her actions unintentionally shape his future as a ruthless tycoon.