Didibhai is the story of a brother and sister who get separated when their parents are murdered by two goons. Partho is brought up by a woman and Urmila by a lady doctor. Urmila grows up and falls in love with the local inspector, Rupankar. Partho falls in love with Asha. Circumstances reveal that Asha’s uncle is the murderer of Partho’s parents. He takes revenge and is reunited with his elder sister.