Ralph Jackman

 is an advertising agent at McMann & Tate.

Ralph steals the layouts for the Illinois Meatpackers account from Larry Tate's office safe. While at the airport waiting for his flight to Chicago, he sees Darrin and Samantha. Stopping to speak with the Stephenses, he accidentally switches his briefcase with Darrin's then leaves on his flight.

Larry and a security guard arrive soon after Ralph leaves and the four of them discover that Ralph accidentally left his briefcase with the stolen layouts.

That evening, Ralph visits Darrin at home to explain things. While there, Endora tries to cast a spell upon Darrin to turn him into a mouse. Darrin is protected by a counterspell, however, and Ralph is turned into a mouse instead.