When villagers begin disappearing it is discovered that they had fallen through a crack in the earth which goes straight to Hades. Hercules once again comes to the rescue and faces one of his most difficult challenges, and must prove himself as a man as well as a god. "Hercules in the Underworld" is the fourth made for TV movie in the series Hercules: The Legendary Journeys.

The eternal Hercules in this film has gone way beyond his usual time and place in ancient Greece and is now helping Poland free itself of Mongol invaders in the 12th century. Mark Forest is the star of this peplum epic, Hercules Against The Barbarians.

Two boxing promoters travel via time machine back to the days of Hercules, who must save them from Genghis Khan and the Mongol Horde.

Hamilan, a cruel and ambitious general, murders his king and places himself on the throne with the former king's evil niece as his queen. He then wages war against his peaceful neighbors, killing their women and enslaving their men. A hero named Ursus appears at a tournament to challenge Hamilan's authority. Though victorious at the tournament, Ursus is arrested and forced to turn a grist-mill under an overseer's lash. Meanwhile, the former king's virtuous daughter, Diana, is tormented by her evil cousin, the new queen. Sentenced to a slow and tortuous execution, Ursus breaks free and a revolt breaks out. Ursus throws Hamilan to his death in a fiery pit and then Ursus and Diana enjoy the cheers of a grateful populace. - Written by dinky-4 of Minneapolis