Despite the title, the two segments remained separate and did not crossover with one another. Fred, Barney and the Thing were only featured together during the show's opening title sequence and in brief bumpers between segments. The unusual combination of a Marvel superhero and The Flintstones was possible because, at this time, Marvel Comics owned the rights to several Hanna-Barbera franchises and were, in fact, publishing comic books based upon them; The Flintstones was one of these.