 After two seasons of the "Super Friends" cartoon, it was cancelled, though re-runs were shown through 1976.When the show returned as "The All-New Super Friends Hour" in 1977, Wendy and Marvin had been replaced by two other teenagers, Zan and Jayna, the Wonder Twins, along with their pet, the alien monkey Gleek.Marvin and Wendy did not appear on TV again for another 35 years, and they were also replaced by the Wonder Twins in the "Super Friends" comic after "graduating" from the Super Friends as full-fledged superheroes.