In this article for sixth-formers and school teachers, I explore the story of Achilles' heel and Homer's likely suppression of the myth in the Iliad. Homer's Iliad appears to acknowledge, but simultaneously reject, an alternative tradition in which Achilles was more than mortal, part of a broader downplaying of heroic invulnerability and immortality within the poem. The only way to achieve immortality in the Iliad is through the fame and glory provided by Homeric song