The episode: “Jack Frost,” ep. 607
The riff: Sarcastically spoken by Mike as the movie’s title character, Jack Frost, saunters into the frame. He’s a round-faced man with a long, white beard.
The explanation: A multi-part joke with two references. Bob Keeshan was a television actor known to millions as the title character of “Captain Kangaroo” from 1955-1984. Jack Frost has a very similar face in this movie, but his comical beard was more akin to “Mr. Natural,” the famous creation of underground “comix” artist R. Crumb in the 1960s. The character was cast as something between a phony guru and a criminal con-man. Of note: This has nothing to do with the famous MST3k short “Mr. B Natural.”
Novelty factor: I recognized the “Mr. Natural” reference because a previous riff led to me reading about R. Crumb (I don’t remember which). Bob Keeshan I didn’t know, although I am familiar with Captain Kangaroo. The character made some great appearances in “Black Dynamite.”