Be warned: this story is beautiful but tragic. It begins with Orpheus, the best musician that ever lived. One strum of his lyre, one note sung, and beasts would crawl to him, rocks would shift their moss to move to be closer, trees would tear their roots to be closer to him. He had more power than a mortal man ought to for he was the son of the Muse Calliope.
He lived his life simply and carelessly until the day he met Eurydice. She was a Dryad, and when they fell in love it meant everything to them. But the rustic god Aristaeus saw Eurydice's beauty and desired it, and did not care that she was unwilling and in love with another. She ran from him in terror, without thought to her step, and so it was she stepped on a poisonous snake in her flight. The venom of its bite killed her at once and her spirit went to the Underworld. Orpheus was inconsolable. His grief was bitter, but he did not let it lull him into a stupor, he decided to take action.
With his lyre, Orpheus descended into the Underworld. A normal mortal would have perished any number of times, but Orpheus had his lyre and his voice and he charmed Cerberus - the three-headed monster dog of Hades who guarded the Underworld - into letting him pass. Facing Hades and his cold Queen Persephone he played for them his sorrow at the loss of his love. The heart that was frozen by Hades' abduction melted in Persphone's breast and a tear rolled down her cheek. Even Hades could not help weeping. They let Orpheus through to Eurydice, but warned him very carefully: Eurydice would follow him into the light of the world and once she entered the sunlight she would be changed from a shade back to a woman. But if Orpheus doubted, if he looked back to see her, she would be lost to him forever.
Orpheus heard and rejoiced. He turned and left the dark hall of Hades and began his ascent back to life. As he walked he rejoiced that his wife would soon be with him again. He listened closely for her footfall behind him, but a shade makes no noise. The closer to the light he got, the more he began to believe that Hades had tricked him to get him out of the Underworld, that Eurydice was not behind him. Only feet away from the light Orpheus lost faith and turned around. He saw Eurydice, but only for a moment as her shade was whisked back down among the other dead souls. She was gone.
Orpheus tried again to enter the Underworld and demand her return, but one cannot enter twice the same way - and no other way was open to him. All that was left to him was death. Here the story changes. There are different stories of his death. Some say he played so mournfully that his songs called for death, and that the animals who surrounded him tore him apart, weeping as they did. Some say it was Maenads in a frenzy who ripped the singer to shreds. Some say he was struck down by Zeus for disclosing mysteries that were meant to be kept sacred. Either way, he was torn apart, and much of him was thrown to the winds. But the Muses mourned the death of their son and prodigy, and saved his head to sing forever.