This 30-minute Saturday morning cartoon was produced by Ruby-Spears Productions and aired a total of 26 episodes. The first season, called "Heathcliff and Dingbat," ran for 13 episodes and included backup segments with Dingbat and the Creeps (who were created specifically for this show). The second season, called "Heathcliff and Marmaduke," ran for 13 episodes and featured backup segments with fellow comic strip character Marmaduke.
Heathcliff goes to the carnival and runs into Crazy Shirley. Can Heathcliff dodge the crazy-about-him girl?
The Winslow family goes to watch a rocket launch and the rocket is being piloted by a robot named Bruce when Marmaduke chases a cat into the rocket and it blasts off. Can Bruce the robot keep Marmaduke from messing up the mission and can Marmaduke return to earth to his family?...more+
Barbie takes a dare that she and Billy can stay in a haunted house for an hour and they bring Maramduke with them. Can they stay there for an hour with the ghost of Captain Clum trying to scare them away?
Barbie and Billy Winslow go to play a baseball game and reluctantly bring Marmaduke along to be the mascot. Barbie has to sit out the last inning and Marmaduke steps in to take her place with their team down one to nothing. Can Marmaduke help the team win the game?
An alligator escapes from the zoo and is really hungry when he spots Heathcliff going through some garbage cans. Can Heathcliff avoid the alligator and keep from being on the menu?
Marmaduke and the kids are playing in the park and Mr. Nicely is watching them play when J. D. Taggart drives up and says that he is repossessing the lot if the loan is not paid quickly. Can they raise enough money in time to pay off the loan and save their playground?...more+
Marmaduke sees a female bulldog named Missy and he instantly falls in love with her but there is a male bulldog that lives in the same yard with her and he doesn't like Marmaduke. Will Marmaduke win her over or will the other bulldog keep Marmaduke away?