Super Friends (1973) : 5x6

The Man in the Moon: Superman must save Earth from a giant alien beast. Circus of Horrors: While at the circus, the Wonder Twins and Gleek witness the revenge of circus animals as they zap the audience in a trance. The animals capture Gleek and zap the Wonder Twins as well, who they send off to lure Superman and Wonder Woman into a trap at the circus. Around the World in 80 Riddles: Superman brings a new engine for the Bat-jet to the Bat-Cave. However, when Batman opens it up, he finds the Riddler hiding inside. He hops out and spritzes Superman, Wonder Woman, Batman, and Robin with stupid spray. There is only one antidote and the Riddler has hidden it somewhere. If the Super Friends do not find it before the time limit is up, they will be super-stupid forever.