First aired: 1980
It did happen… there was a cartoon version of Happy Days, with the Fonz (Henry Winkler) as the central character, and they did meet a vampire. The series added in an anthropomorphic dog called Mr Cool (Frank Welker) and took the premise that Fonz, Richie (Ron Howard) and Ralph (Don Most) met a time traveling girl named Cupcake (Didi Conn) and ended up lost in time with her.
|Cupcake and the Crap Bat|
I have some rose-tinted memories of Happy Days, but not, alas, the cartoon and it seems to me that it was a tie in too far. Never the less it was a fair way to mindlessly spend 20 or so minutes and the voice acting being provided by the live action Happy Days cast (where applicable) was positive – as was the intro by Wolfman Jack. Still, it really was a tie in too far. 5 out of 10.
The episode’s imdb page is here.