Answer:
When Odysseus' advance party discover Circe's palace in the middle of the forest, Circe [Falcon] invites them in and gives them a meal. The men all behave disrespectfully so Circe makes the food with a magical poison, and all of the sailors are transformed into pigs, except Eurylochus - who expected a trap and has eaten nothing.
Eurylochus escapes and warns Odysseus. Odysseus sets out to rescue his men, but is intercepted by Hermes. Hermes tells Odysseus that he can resist Circe's poison by using the herb Moly. Odysseus convinces Circe to release his men and then There is then quite a lot more story - but at the end Odysseus leaves with his men, and they can continue with their journey.
Odysseus sent some men out and those men were turned into animals. When Odysseus tried to set them free she said she would not do it unless he lay with her.