The Story of Perseus
Perseus was the son of Danae and Zeus, who appeared to her as a shower of gold. Perseus grew up on the island of Seriphos, in the house of King Polydectes.
Polydectes took a shine to Danae and tried to force her to marry him. Danae was unwilling, and Perseus defended her from his attentions.
Polydectes played a trick on them. He pretended he wished to marry Hippodameia, daughter of Pelops, instead, and asked all his friends to contribute one horse each as a love-gift. Perseus had no horse. 'But if you intend to marry Hippodameia,' he said, 'I will win whatever gift you name - even the head of the gorgon Medusa.' This amused Polydectes and he accepted.
Medusa and her sisters Stheno and Euryale were gorgons - dreadful monsters in the form of ugly women with serpents for hair, huge boar's teeth, a tongue sticking out, and golden wings. They were so hideous that anyone looking at them was turned to stone with terror. So Perseus had made a daring boast.
The Gods Help Perseus
To help him in this quest Athena gave Perseus a polished bronze shield, and told him to only look at the gorgons' reflection in it, so he would not be turned to stone.
Hermes also gave Perseus a sword (or a sickle) with which to cut off Medusa's head. But he told Perseus he would also need a magic sack to carry her head, the helmet of invisibility belonging to Hades, and a pair of winged sandals. All of these items were in the care of the Stygian nymphs - but the only ones who knew their whereabouts were the Graeae.
The Graeae were three swan-like women, sisters of the gorgons, who were fair of face but had had grey hair from birth. They also had only one eye and one tooth between them.
Perseus found their cave at the foot of Mount Atlas. Creeping up behind them he snatched the eye and the tooth. Blind, they could not find him, and begged for the eye and tooth to be returned. Perseus refused unless they would tell him how to find the Stygian nymphs, and at last they did so. The Stygian Nymphs were happy to give Perseus the sack, sandals, and helmet.
Perseus found his way to the lair of the gorgons. Following Athena's advice he looked only in his shield and saw the gorgons asleep. Swiftly he chopped off Medusa's head and thrust it into the bag. To his surprise the winged horse Pegasus and the warrior Chrysaor sprang from Medusa's dead body and woke her sisters. Perseus donned the helmet, became invisible, and flew away.
As Perseus flew over Palestine he saw a beautiful naked woman chained to a rock, and instantly fell in love with her. This was Andromeda, the daughter of King Cephus
of Joppa and Queen Cassiopeia. Cassiopeia had boasted she and her daughter were more beautiful than the sea nymphs, and so Poseidon had sent a flood and a sea monster to devastate Palestine. An oracle had said the only hope of salvation was to sacrifice Andromeda to the monster, which is why she was chained to a rock.
Perseus made the king promise that Andromeda could be his wife if he saved her from the sea monster. Then he swooped down on the beast and beheaded it with the sword.
Back in Seriphos, Perseus found that Polydectes had been lying and was still bothering Danae. He went to the palace and told the court he had indeed slain the gorgon. Polydectes and his courtiers laughed and insulted him, whereupon he took Medusa's head from the sack and turned them all to stone.
Perseus gave Medusa's head to Athena, and she wore it on her breastplate - you can see this in pictures and statues of Athena. Later he is said to have been the father of the Persians - the Greek word for Persians is Persae, from Perseus.
Athena with gorgon's head
Perseus with Medusa's head. By Cellini.
Perseus rescues Andromeda
Perseus Arming, by Gilbert, 1883 - Bolton Museum