This is an unusual third-season episode where all the erstwhile regulars make an appearance. Plus recurring characters Exidor and Miles Sternhagen.
Final appearance of Miles Sternhagen.
The title "I Heard It Through the Morkvine" is based on the popular tragic love song "I Heard It Through the Grapevine" written by Norman Whitfield and Barrett Strong in 1966. It was recorded by a variety of artists, with Marvin Gaye's version being the best known.