Shupanakha awoke, and called out for her brother. Lakshmana had gouged out her eyes, and she blindly stumbled around the room screaming in rage. Ravana arrived and demanded to know who had done this to her. She told him that Lukshmana had caught her and mutilated her, and that he was in the forest with Rama and Sita. A sage who was forced into Ravana's service stepped forward, and offered a revenge curse. "Ravana, if you go to them and mutilate Lakshmana, and then bring back Sita, we can sacrifice her. This will restore your sister's body, and make her as beautiful as Sita." explained the sage.
Ravana met with his uncle Maricha and told him what had happened, and how the revenge curse could heal Shupanakha. "I am leaving for the woods where Rama is camped, and you will join me in avenging our sister." barked Ravana. On their way to Rama's camp, Ravana devised a plan. Rama was too powerful, and couldn't be defeated in combat. Instead, Maricha would distract him and lure him away from the camp. Then Ravana would ambush Lakshmana, mutilate him, then steal Sita. In the woods outside Rama's camp, Ravana hid in a tree and ordered Maricha go and lure Rama.
As Ravana was perching in the tree, he saw a golden deer run under him. The golden deer dashed through the woods, with Rama in pursuit. As soon as Rama was out of sight, Ravana ran to Rama's camp. Rama spotted the hut that Sita and Lukshmana were in. He snuck up to the door and knocked it down, then burst into the room. When the dust cleared, Ravana laid eyes upon Sita and froze in his tracks. This was the most beautiful woman he had ever seen. He lusted after her, and decided that he would take her back for himself. He wasted no time dealing with Lakshmana, grabbed Sita, and headed back to Lanka.
Ravana abducting Siva, Wikipedia
Author's note: This story was inspired by Narayan's The Ramayana. This story is an alternate version of events after Shurpankha returns to Lanka. I wanted to show Ravana as a truly evil character who is only concerned for himself.
Bibliography:
Narayan, R. K. (1972) The Ramayana