Chronic Bachelor movie is about life of Sathyaprathapan (Mammootty) who lost his father when he was very young. His father Balagangadharan had in Neelakantan, a very bitter enemy. And Neelakantan had done all that he could do to make Balagangadharan's life intolerable.
Anyhow, after Balagangadharan's death, Neelakantan turns to Sathyaprathapan and instills in his mind the notion that his father was not a good man. And pretending love, Neelakantan cleans away all of SP's property.
Later only does SP realise the truth. He then starts life afresh with the help of Parameswaran, who makes him realise that his father is not what Neelakantan had made him out to be. And then SP works hard and becomes a successful businessman.
He had, in his earlier days, loved Bhavani, the young daughter of Neelakantan. But when Bhavani stood by her father in cheating SP, he turned bitter at heart and pledged to remain a bachelor all his life. He lives along with his friend PA Kuruvilla, who too has decided to remain a bachelor.
In the meantime Bhama and some other young girls come to stay at a house opposite SP's house. And SP's house too has some new members. There is young Sreekumar, son of Parameswaran and his friend Ugran, who too have come to live with SP.