Super Friends (1973)

S4E5 Universe of Evil

In an alternate dimension, the Super Friends have transformed into the Super Enemies. Mount Vesuvius serves as a crucial connection between their worlds—where Superman is desperately trying to prevent the volcano from erupting, his malevolent doppelgänger is instigating the eruption in his universe. When Vesuvius erupts, the two Supermen swap places. Now, Superman must contend with his wicked adversaries while searching for a way to return home, while his evil twin faces the genuine heroes and sets his sights on dominating Earth.