The Adbhuta Ramayana is composed in 27 sargas of various metres, and only briefly recounts the traditional Rama narrative.
This adaptation of Rama's life begins with his confrontation with Parashurama as he and his family returned from his wedding in Janakpura.
The rishi Bharadvaja approached Valmiki and asked him to narrate the story of Rama, reminding him that the Ramayana includes hundreds of thousands of shlokas (verses), most of which have been unavailable.
Bharadvaja asked to hear one of those secret stories, to which Valmiki agreed, noting that this version would emphasize the deeds of Sita, the incarnation of Prakriti (nature).
Ambarisha had a daughter named Shrimati (she was an avatar of Lakshmi, who later took the form of Sita), who was beautiful and famous for her virtues and good qualities.
The sages Narada and Parvata each desired her for a wife (they did not know Shrimati's true form), and so Ambarisha—unable to choose one without incurring the wrath of the other—arranged her svayamvara so that she could decide who should be her husband.
Narada and Parvata then independently approached Vishnu, asking for each other to unknowingly appear in the disguise of a monkey, which only Shrimati could see.
Narada and Parvata attended the svayamvara, both appearing to Shrimati as monkeys, but each imagining himself handsome and irresistible.
His fame spread to the king of Kalinga, who demanded that Kaushika sing devotional songs to him rather than to Vishnu.
Millions of celestial maidens attended, as well as Lakshmi, the consort of Vishnu, with her retinue of maid servants.
Emboldened by Brahma's boon, Ravana began his attempts to conquer the three worlds, but his reckless behavior set in motion the events leading to the birth of Sita from his wife Mandodari.
At that moment, the earth shook with great peals of thunder, and flashes of lightning lit the sky.
The story quickly moves forward to Sita's abduction by Ravana following Rama's exile into the Dandaka forest.
In the court of Ayodhya, in the presence of saints and seers, Sita noted that the slaying of Ravana was not that big a deal.
When she was very young living in her father's home in Janakpura, a Brahmin had passed through and told her of Ravana's older brother Sahastra Ravana, who had two thousand arms and a thousand heads, lived on an island named Pushkara, and was originally much more powerful than his younger brother.
Rama collected his army of monkeys, men, and rakshasas, and departed to conquer Sahastra Ravana.
Employing the vayavastra weapon, he dispersed Rama's army to the places from which they came: the men to Ayodhya, monkeys to Kishkindha, and the rakshasas to Lanka.
Seeing Rama unconscious and helpless on the field, Sita got angry, and giving up her human appearance, she took on the exceedingly horrific form of Mahakali.
Innumerable mothers of every type came to the battlefield to sport with Mahakali, playing games with the heads of rakshasas.
Brahma explained to Rama that she had taken this form to highlight the fact that everything he does—the creation and destruction of the universe, and all other activities can only be accomplished in association with her, with shakti.
She then gave Rama “celestial sight” so that he could perceive her divine state (due to Narada and Parvata's curse, Rama forgot that he was the Supreme Being and thus Sahastra Ravana could make him unconscious and he needed celestial sight to see Sita's divine form).