This episode marks the return of the original theme music, including the bongo drums.
This was the debut of Lynda Day George in the role of Lisa Casey. She assumed the roles played by the departed Leonard Nimoy and Lesley Ann Warren, that of disguise expert and leading lady.
In this episode, Peter Graves' character has to be rendered blind temporarily. Years later, Peter Graves would guest star in a episode of Fantasy Island, as a blind detective who regained his sight back temporarily, in order to fufill his fantasy of solving the case of a missing actress.
As a necessity to guard against a reflex action that would reveal his "blind" pretense, Phelps is forced to have opaque contact lenses surgically implanted. Evidently the eye drops used to "blind" Cinnamon in the season three show "The Heir Apparent", were discarded or forgotten.