Achilles was the son of Thetis and Peleus. His mother tried to protect him from a prophecy of early death by dipping him into the River Styx, which would make him invulnerable. However, she held him by the heel so his heel was unprotected. She sent him to hide in the court of the king of Scyros, where he was disguised as a girl and married the princess Deidamia. Odysseus disguised himself as a traveling merchant, and tempted Achilles into revealing himself using a beautiful sword.