5x13 - Hercules: The Legendary Journeys

Hercules jumped through a vortex into the Netherworld. There he found his evil double, the Sovereign, as well as the cowardly double of his late sidekick, Iolaus. Disguising himself as the Sovereign, Hercules learned that Nebula, the parallel world's evil ruler, conspired with Ares to imprison the Gods of Olympus in the Labyrinth of Eternal Memory. Hercules and Iolaus battled a giant snake and entered the labyrinth. After defeating Ares and Nebula, Hercules freed the gods. The parallel Iolaus, wishing for a bright future in a new world, jumped through the vortex with Hercules.