Once long ago, Ravana will be trying to rape a woman called Vedavathi. She pleads Lord Fire to take her life away, which Fire God does so. This Vedavathi will be with Lord Fire until she is reborn as Mohini to the king of Sheelnagar. She would have given her heart to Vishnu by then.
Narada, on his way back from Vishnu after boasting, suddenly sees Sheelnagar, which is bright in colours. The King visits Narada and informs him that ‘colours’ are due to his daughter’s swayamvara. King invites Narada to see his daughter and give her blessings. Narada goes to palace to see daughter.
Narada is star-struck upon seeing the daughter, Mohini. He blesses her, but goes back to Vishnu again and asks him to make him into a unique person so that he can compete in Swayamvara whereupon everybody should just stare at him (read handsome). But Vishnu makes him into a monkey-faced man (as a punishment to his pride) and considering and manipulating Narada’s own words of ‘unique person to be stared at’.
Everybody in Swayamvara laughs at Narada when he enters the swayamvara. (He has not seen his own face). Obviously he is rejected. At the Swayamvara, Vishnu suddenly appears and Mohini immediately garlands him and accepts him as her husband. She is apparently done some form of tapas or so, and is grateful that Vishnu has accepted her as his wife. Then she takes her place (resides) in his heart (after minimizing herself!!)
Narada leaves the palace, disgusted at Vishnu, wondering why Vishnu played a dirty game even though knowing that Vishnu himself would be declared as hubby. On his way back, Narada looks at his face reflection in the palace fountain. He is shocked to see the monkey face. His rage towards Vishnu is uncontrollable. He transforms to his original swami self and goes to Vishnu. Immediately upon arrival, he curses (‘shaap’) Vishnu that one day he will go to Earth and his wife will be separated from him and that he will beg to a monkey for the return of his wife. Thus starts Avatar # 7: Rama Avatar.