This is an Ancient Greek myth, about a man called Orpheus who journeyed to the Underworld to save his wife.
Orpheus was a famous musician in Greece. He could play the harp like no other. He played songs so beautiful that even the trees and rocks sprang up to dance.
When Orpheus' wife Eurydice was bitten by a snake and died, Orpheus was distraught. His songs became so sad that the gods cried out and finally gave him the advice to journey to the underworld to reclaim her soul from the bowels of Hades.
Orpheus soon travelled to the Underworld and crossed the river Styx with the help of the ferryman Charon, even though he was not dead.
He journeyed through the many perils of the Underworld, from the monstrous three headed dog Cerberus to the many howlings of lost souls long dead.
Finally he reached the king of the Underworld, Hades himself, and his queen Persephone and begged for Eurydice's soul back. He played his harp for them, and even the lost souls wept at the very sound. Persephone called forth Eurydice.
Orpheus could take Eurydice back on one condition: that he would walk back to the land of the living but not look back once. Eurydice would walk behind him all the way.
Onwards Orpheus walked, always hearing the footsteps of Eurydice behind him until he reached the gates of Hades. The footsteps behind him stopped, though he continued to walk. Forgetting himself, he turned around to see Eurydice being pulled back down to Hades.
Orpheus wept and begged Charon to take him back across the Styx but he refused. Orpheus begged for seven days but to no avail. He returned to the world of the living and swore off love for the rest of his days.