 An enchantress , disguised as an old beggar , offers a rose to a young prince , in exchange for shelter in his castle from the cold , but the prince refuses . For his arrogance , the enchantress transforms him into a beast and places a spell on the castle . She gives him a magic mirror that enables him to view faraway events , along with the enchanted rose that she had offered . To break the spell , the prince must learn to love another and earn her love in return before the rose 's last petal falls on his 21st birthday . If he fails , he will remain a beast forever . 
