Hercules: The Legendary Journeys

Cerberus: Cerberus is the multi-headed dog that guards the gates of Hades. While most versions depict him as having three heads, some versions say two, and some say 50. He was a child of Echidna and Typhon. When Hercules refers to his previous encounter with Cerberus, he's referring to their meeting in the Hercules movie "Hercules in the Underworld". Hercules also has a connection to Cerberus from the final of his 12 Labors for King Eurystheus. He was ordered by the king to capture Cerberus alive without using weapons. Hercules was able to overpower Cerberus and slung the beast over his back, dragging it out of Hades through a cavern entrance and presenting it to Erystheus, who was so frightened of the dog he begged Hercules to return it and released him from performing any more Labors.

Women in Tartarus: (emptying leaking buckets into a well) We cannot rest until we fill the well. These women are the Danaides, fifty sisters who were married against their wills by their fifty cousins. 49 of them murdered their husbands on their wedding night at the instruction of their father, Danaus, while only one, Hypermnestra (or Amymone, the "blameless" Danaid) refused because her husband, Lynceus, honored her wish to remain a virgin and helped her husband escape. As punishment they spend eternity trying to carry water in leaking buckets only to have the water all run out before they can get to the well.

In the myth Persephone eats six pomegranate seeds, a fruit associated with the chthonic deities. So the six seeds equal six months in the Underworld for Demeter's unlucky daughter, not by her own choice, but by Zeus's decree.