Famous scientist Dr. Joygopal Mukherjee believed that if upper caste blood mixed with lower caste blood, there must be an degradation not only by the genetic but it also affect the action. Dilip was his only son. He had been educated in a very modern way. Apart from that a learned Brahmin had been appointed as a house teacher. But one day Dilip discovered that his ideology was different to his father. He felt all human being were equal, difference is unjust, is sin of his father and son. Dinabandhu has bought up her dancer daughter Amita Paul in a very liberal way. Amita had an inborn quality to get the heart of others. So in the first day meeting she could impress Dilip, Dilip's mother Bijaya and his father Joygopal. Dilip and Amita became closer. Amita realized that one day the difference of caste would create problem between them. That happened also, but Dilip inspite of all situation married her. After marriage Dilip tried but could not secure a job, so he was forced to stay in the slum. He started drinking. But Amita still remained what she was before. She was quite happy with her son and Dilip. At last Joygopal came to Amita and confessed that his theory was wrong. His grandson had proved his five hundred page theory wrong.