Nebula (Gina Torres) enters a Sumerian temple and finds Hercules (Kevin Sorbo) grieving over Iolaus' (Michael Hurst) lifeless body. Refusing to accept the fact that Iolaus is dead, he tells Nebula he is going to the Sumerian version of the Underworld to bring his friend back. Despite her warnings, Hercules leaves Nebula's castle and heads towards the jungle to find the entrance to the Underworld. On his way, he encounters an old woman (Wanjiku Kiarie) with a strange marking on her hand who is a servant to the gods. She urges him to continue his journey and as he does, he discovers that Nebula and her crew have been tracking his movements. After Nebula convinces Hercules to join forces, the group presses on through the jungle. As they get deeper into the undergrowth, Nebula's men have some serious reservations about their mission. After encountering several evil markings, Danaeus (Paul Glover), one of Nebula's favorite crewmen, questions Hercules about his power and motives. Hercules scolds him so severely that the young man runs off into the darkness. Danaeus is later found dead, with his body strangely emaciated and his pupils blackened.
The next day, the crew is traveling up a river in canoes when they come across a wrecked ship. When a body with gray and withered skin like Danaeus' floats by, Hercules and Nebula realize that this was no accident. The entire crew board the vessel and find more bodies in the same condition. Suddenly, the dead bodies start to move. As the zombies begin to attack, Hercules discovers that the only way to kill them is to burn them. As the fight ends, a zombie scratches Nebula, drawing blood.
Considering the danger in completing the journey, Nebula and Hercules send the rest of the crew back home. Soon, Nebula's behavior becomes erratic and Hercules notices that the skin around her scratch is now gray and withered. Suddenly, Nebula runs off and Hercules finds her at the entrance to the Underworld. Struggling against the voice being projected into her from the Underworld, Nebula attacks Hercules. Careful not to harm her, Hercules manages to tie her up. He then repels down into the cave to confront Dumuzi (Antonio Te Maioha), the Sumerian God of the Underworld. When Dumuzi appears in a hall of mirrors, he claims that he must steal human souls to survive, since the sacred chalice that provided nourishment for the gods was recently destroyed by Hercules' enemy, Dahak. Dumuzi continues to taunt Hercules and the two begin to fight. During the struggle, Dumuzi tells Hercules that Iolaus had already crossed over to the Underworld before he started collecting souls, and is lost forever. Devastated, Hercules cries out Iolaus' name with such rage that the mirrors surrounding the god's lair shatter. Shards of glass slice Dumuzi to shreds, destroying the god and freeing the trapped souls.
Hercules and Nebula return to her castle where Nebula recovers. When Nebula decides to stay with her people, she gives Hercules her boat and bids him farewell as he sails off towards a dark horizon.
Starring: Kevin Sorbo (Hercules), Michael Hurst (Iolaus)
Guest Starring: Gina Torres (Nebula), Antonio Te Maioha (Dimuzi), Wanjiku Kiarie (Old Woman), Ronald La Pread (Priest), Tony Hopkins (Agenor), Paul Glover (Danaeus), Grae Burton (Crewmember)
Written by Lisa Klink
Directed by Richard Compton