'Hal Smith (I)''s character, Otis Campbell, was the town drunk in the original series. In this reunion he's now sober and is the town's ice cream man.
Frances Bavier, who originally played Aunt Bee in the series, was ailing and homebound when this movie was made. She considered recording a brief audio segment but decided against it. Another actress does that part, which is heard as Andy lays a flower on Aunt Bee's grave.
By 1986 the original outdoor set from The Andy Griffith Show had been destroyed, so the Mayberry town square had to be re-created in a small town in California. This results in the road that originally came to an end in front of the courthouse now going straight on by, being much wider, and a flagpole being in the middle of the street.
Charlene Darling appeared on the series with a husband, Dud Wash, and later an infant daughter Andilina. However, in the movie, when she appears there is no mention of Dud or the daughter.
The sub-plot of the lake monster was inspired by the infamous Lake George monster hoax in New York's Adirondack Mountains.