In the Odyssey, how did Circe trap some of Odysseus' men?

During Odysseys' journey home he visits many different islands and meets many different people. One island he goes to is Aeaea, where the goddess Circe lived. When the crew reached shore Odysseus sent a group of his men to explore the island. The men stumble across the home of the goddess Circe, where they saw strange creatures such as lions and panthers. Circe lures them into the house and offers them food and drink. However, it was actually a trap. The goddess uses her magic to turn the men into pigs, who Odysseus has to later rescue.