To me, sirens are best described as "evil mermaids". They lure passing sailors in with their song, and then pull them into the water. In The Odyssey, Odysseus’s ship passes by the sirens. Every other sailor had their ears plugged - but Odysseus wanted to hear their voices. So he had his crew tie him to the mast and told them that, no matter what he said, not to untie him as he would surely drown himself. In the movie, the siren's voices are that of his wife, Penelope, and his son, Telemachus, telling him he’s home, cursing him for leaving, saying that they have forgotten the look of his face.