Spiced with modern cinematic elements, this exquisitely crafted musical revolves around a plot by Ravi Varma (Sreenivasan), Kesava Pillai (M.G Soman), Prabhakara Varma (Karamana Janardhanan Nair) and Rajaraja Varma (Maniyanpilla Raju) to kill King Udaya Varma Thampuran(Nedumudi Venu) to amass his wealth.
Udaya Varma's wife Bhagirathi Thampuratti(Kaviyoor Ponnamma) has fallen into depression after the untimely death of their son Unni. She is locked up at home and looked after by Udaya Varma's daughter Radha (Gautami). Ravi Varma and group fears that Udaya Varma might will his wealth to Radha, being his daughter, who is believed to be born of Thampuran's illicit relationship with his maid. The group is helped by Cheriyachan Thampuran(Thikkurissy), a blind cousin of Thampuran, who also eyes at King's wealth.
He advises the Group on the plans to eliminate the King upon condition of sharing the wealth with him. As per his advice Ravi Varma travels to Mumbai in search of a killer. There he meets Jamal(Mammukoya) who helps him. He introduces Ravi Varma to Abdhullah(Mohanlal), who is a singer in Mumbai. Abdhullah is in need of money and upon persuasion from Ali, goes to Kerala planning to kill Thampuran.
Abdhullah disguises himself as Ananthan Namboodiri and meets Thampuran stating that he is Ravi Varma's friend who wants to study about the palace. Thampuran does not like this, however allows him to stay a couple of days at the Palace. Bhagirathi thinks Ananthan is Unni and shows stages of recovery from mental disorder with his presence. Once the day Thampuran asks Ananthan to leave arrives, he sings the famous Pramadhavanam song which impresses Thampuran and he starts liking him. Radha falls in love with him.
Ananthan is even permitted to dine with Thampuran after having developed a strong relationship with him. Gupthan(Jagadeesh) on finding that Radha is in love with Ananthan, misleads Ramanattukara Ananthan Namboodirippadu(Kaithapram), a famous musician, telling him that Ananthan has portrayed him as a good for nothing fellow. Enraged by hearing this Kaithapram travels to the palace and compete with Ananthan, singing the famous Devasabhathalam after which he understands that Gupthan mislead him.
Ravi Varma and group wants Thampuran to be killed immediately. Ananthan one day realises that Thampuran is an old friend of his father. Thampuran also says Ananthan that Radha is not his daughter but she was brought up by him as his daughter after the demise of Unni. Thampuran also requests Ananthan to marry her. Ananthan, unable to kill Thampuran pleads to the Group that he cannot kill him.
The group gets angry and Ravi Varma travels to Mumbai to find another killer. He comes back with Karim, a goon from Mumbai to kill Thampuran. Thampuran, identifies that Ananthan is a Muslim named Abdullah when he accidentally sees Ananthan performing Daily Namas.
Ananthan tells Thampuran that he is surrounded by enemies and he can save him. But Thampuran denies. Next day morning Thampuran is found to have disappeared. Karim and other goons try to find Thampuran and indulges in a fight with Ananthan. Ananthan, overpowers him and the Group and they all runs away from the palace. After the fight is over, Ananthan releases Thampuran, whom he had locked up in a room in order to save him from Karim. Thampuran shockingly realises that Ananthan is his friend's son and feels sorry for having disbelieved him. He requests Ananthan to stay in the palace as Unni and marry Radha. Ananthan accepts the request from Thampuran.