Orpheus and Eurydice.

 Orpheus (Ὀρφεύς) was a singer. His parents were Apollo and Calliope. His symbol was a lyre. Orpheus played on this musical instrument. His music was very beautiful.

When Orpheus was a young man, he took part in the campaign for the Golden Fleece. He was with Jason and the Argonauts.

Eurydice (Εὐρυδίκη) was a forest nymph or dryad. She liked music of lyre which played by Orpheus. Later they understood that loved each other. 

Orpheus and Eurydice (Ὀρφεύς καί Εὐρυδίκη) got married. They became happy. But unfortunately it didn't last long. Eurydice was bitten by a snake in the forest. She died.

Her husband Orpheus was very sad about it. He decided to return Eurydice to this world.

Orpheus went to the underworld. Eurydice's husband sailed on the river Styx. He met Cerberus (Κέρβερος), dog with three heads. Also, Orpheus played on his lyre for Hades (ᾍδης) and his wife Persephone (Περσεφόνη).

So, he was able to take Eurydice. But Orpheus shouldn't look at her. She must go behind him. They went together.

Once Orpheus broke down and looked at his wife. Eurydice was left in the underworld forever.

Orpheus had a big griefed. He died.

This legend was popular in ancient Greece. There are many paintings and statues about these characters.