Scooby-Doo had been on a bit of a hiatus when this aired in 1997 (things finally got moving again a year later with the Scooby-Doo on Zombie Island movie), so this was a nice way to remind everyone, and say 'Look! We're still here!'.
The plot is a nice homage to all the usual elements of a Scooby-Doo episode - plus there are one or two little touches aimed more at the 'grown-up' audience 😉
By the way, this episode was pretty significant in terms of the Scooby-Doo voice actors; it was the last time Casey Kasem voiced Shaggy until the TV series What's New, Scooby-Doo? (2002), the last time Heather North voiced Daphne until the film Scooby-Doo and the Legend of the Vampire (2003), the first time Frank Welker voiced Fred since The New Scooby-Doo Mysteries (1983), the first of just two times Hadley Kay voiced Scooby (both in this series of Johnny Bravo), and the first ever time B. J. Ward voiced Velma.
A fun watch. 6.5/10.