The Sundara Kanda forms the heart of Valmiki’s Ramayana and consists of a detailed, vivid account of Hanuman’s adventures. After learning about Sita, Hanuman assumes a gargantuan form and makes a colossal leap across the ocean to Lanka after defeating Surasa, the mother of the nagas, and Simhika, who is sent by the devatas.
In Lanka, Hanuman searches for Sita, and finally finds her in the Ashoka Vatika.
In the Ashoka Vatika, Sita is wooed and threatened by Ravana and his rakshasi mistresses to marry Ravana. Hanuman reassures her, giving Rama’s signet ring as a sign of good faith. He offers to carry Sita back to Rama; however, she refuses, reluctant to allow herself to be rescued by any one other than her husband. She says that Rama himself must come and avenge the insult of her abduction.
Hanuman then wreaks havoc in Lanka by destroying trees and buildings, and kills Ravana’s warriors. He allows himself to be captured and produced before Ravana. He gives a bold lecture to Ravana to release Sita. He is condemned and his tail is set on fire, but he escapes his bonds and, leaping from roof to roof, sets fire to Ravana’s citadel, and makes the giant leap back from the island. The joyous search party returns to Kishkindha with the news.