After taking the eye of the Gray Women and blackmailing them into revealing the location of the nymphs of the North, Perseus and Hermes travel over the ocean of the North to meet the nymphs. The nymphs gifted Perseus with the three magic gifts he needed to defeat Medusa: the cap of invisibility, the magic wallet, and the magic sandals. Finally , Perseus was ready to face the Gorgons, and ventured off to their island.
The Road Back
As Perseus flew over the sleeping Gorgons, he noticed the previous victims of the Gorgons, all turned to stone. Perseus was not afraid, however, stalwart and fearless as he was. As Athena informed Perseus which of the Gorgons he had to kill, Perseus flew down and prepared to strike.
Perseus flew down next to Medusa, ready to strike. Peering into the shield, Perseus sliced off the Gorgon's head with one swift blow. Admiring the trophy, Perseus then stored the head in the magic wallet.
Return with the Elixir
Hearing the commotion, the other two Gorgons woke up and started to pursue Perseus. Wearing the cap of invisibility, however, the Gorgons could not see Perseus, and he flew away, unscathed. Perseus headed back to his island home, and Hermes, seeing his mission had been accomplished, parted ways with Perseus.
All had not been so easy on the way home, however. A dangerous sea monster attacking a princess, Andromeda, stood in his way between a safe journey home and imminent death. He slew the sea monster and took Andromeda home as his wife.
Upon returning to the island, Polydectes did not believe Perseus had slain Medusa. Perseus then pulled Medusa's head out of his magic wallet and showed it to Polydectes thus turning him to stone. After the demise of Polydectes, Dictys, the gracious fisherman who helped Perseus and his mother out of the chest, became ruler of the island. Perseus, his mother, and his wife then sailed to Argos.