Voice Actress Marla Frumkin filled in for Patricia Stevens for the voice of Velma Dinkley when Patricia Stevens could not continue for health reasons. Marla Frumkin played Velma Dinkley From Episode "The Ghoul the Bat and the Ugly" to Episode "The Ransom of Scooby Chief." Marla Frumkin (as Velma) only has one line in Episode "The Ransom of Scooby Chief" - "Have a good visit."
After the first season (from Episode "The Scarab lives" to Episode "The Ransom of Scooby Chief") of this show, the shorts were made with only Shaggy, Scooby, and Scrappy doo. The absence of the characters Fred, Velma and Daphne was due to some of the voice actors involved in the Strike and Emmy Awards boycott of 1980. After Episode "The Ransom of Scooby Chief", Don Messick "had" to replace Lennie Weinrib as the voice actor for Scrappy Doo.