Radhika, a Brahmin by birth, was adopted and brought up by a family of weavers in a small town called Rawal. Dev, whose family has been in the service of Rajpurohits for generations, visits Rawal as a child on the occasion of Janmashtmi. Dev and Radhika meet each other in playing the roles of Radha and Kanha in Krishn Leela and became good friends. Dev said his name is Krishn Kanhaiya, thinking she is mocking with him by telling her name as Radhika. Radhika and Dev one day were playing in a mandir and didn't know that on that day whoever gets married will be together for eternity. While Dev and Radhika were playing with one side of chunnari in Dev's hand and other side in Radhika's hand (as her chunnari got wet and they were drying it by running) they reached at the place where 50 couples were tying the knot of marriage. One agnikund was unused due to the absence of one couple and circled the holy fire seven times and Dev rubbed sindoor on her forehead which she got on her head accidentally while coming out of temple. They tied the chunnari together at mansadevi temple which was got opened from tree and fell on Dev's head. While running,they found the gold coin too. So they got married without their knowledge. Later,that night a priest who was present at Dev and Radhika's wedding comes to Radhika's home and tell her mother and father that Radhika is married. After knowing this, Radhika tries to tell Dev but is unable to meet him again. She continues to apply sindoor on Kanha's feet for the name of his Krishn Kanhaiya as her mother denies to apply on forehead.
Maheshwari (played by Pragati Mehra), the eldest bahu of the Purohits, hopes to inherit Dadaji's property. However, her plans hit a snag when Maheshwari realizes that Dadaji has willed all his property is in the name of Choti Bahu and, if the youngest son doesn't get married by age 23, the property will be transferred to a trust. While hearing Dadaji's conversation with the lawyers and thinking the youngest son is Rohan, she decides to get such a wife for him who obey her fully and transfers all property to her.
[edit] After 12 years
One night after college Radhika misses the last boat back to Rawal but there she meets Dev. Both had feelings for each other. He offers to take her by boat and she agrees. The next day, they again meet and spent time with each other. They didn't know each others names. After that day, Radhika realizes she feels bad that she is getting attracted to someone else and decides not to talk with him again. Then Maheswari decides to get Rohan married before he turns 23. So during the festival of Holi she sees Radhika and thinking that Radhika would put all of Dadaji's property in her name and decides to get Radhika married to Rohan.
Maheshwari sends Dev to Rawal for shagun. Radhika's mother lies to her that rishta is for Chanda (her sister) as she is not ready for marriage, and from Radh's talks Dev also thinks that rishta is for her sister. Later on Dev learns from her mother that its for Radhika and Radhika finds out.
Later on, she finds out from Rohan that Dev is her Krishn Kanhaiya and she tells the childhood marriage truth to Dev. He was going to accept, but under obligations and as an orphan he rejects the marriage and tells her marry Rohan. She tries to make her accept many times, but he refuses. At last she leaves everything to Kanha as she is a great Kanha devotee and believes in childhood marriage too because she thinks if Kanha has united them in such auspicious time then only he is her husband.
Radhika is patriotic about Kanha (Krishna). She strongly believes in him. Due to his blessings Radhika was unable to get married with Rohan, and they couldn't complete seven pheres. A fire started when Rohan was screaming at Radhika. She was saved but Rohan was badly burnt and was taken to the ICU. Dev meets Radhika in the hospital and ask her what caused the fire. She told him that Rohan knows that she loves someone else. Dev got really angry causing her for this situation, accused her so much and said that he hated her for telling Rohan without knowing it was all cause of Krishna's blessings.
Radhika decided to get into their house as choti bahu and wife of Dev without telling anyone about the incomplete marriage with Rohan for gaining Dev's trust back. Rohan's mother thinks Radhika is the cause of Rohan's condition. That's why she talks badly with Radhika when she enters into the Purohit house. Then Dev comes and tells everyone that Rohan has regained consciousness. Everyone is happy in the house. But Rohan got some kind of disease where he feels like a little child. Radhika is now ready to take care of Rohan and to perform all works as choti bahu in their house (like doing pooja and making something special in kitchen for first time) with the grace of her Kanha. She spent the night in Dev's room (Rohan's mother didn't allow her in his room and all others were taken by guests; Dev has to go to the guest house).
But in the end good always wins. Radhika's friend Barkha helps Dadaji recover, and she shelters them while running away from Rohan. Everyone found out everything about Rohan, what he had did to them and Radhika tells the family she was never married to Rohan and how she was forced to act like his wife because he threatened to kill Dev. Dadaji recovers and tell the whole family that Dev and Rohan are step-brothers. He tells him that Dev is his small grandson. He tells them that his son was married to Chaaya, Dev's mom. He didn't want Dev to punish and ask Chaaya for him — since then he never saw Chaaya again. Padma slaps Rohan and kick him out of the house. Maheswari Devi becomes a servant because Dadaji told the family what she had do to him all these years and who had actually pushed him down the stairs. She and Virat are treated like servants. Dadaji promises Dev that he will marry Radhika. Radhika goes home and reached hardship when she was there. Dev and Radhika are soon to be wed, but because of social norms every one is calling Radhikha an uncaste woman. Everyone is losing trust in the Raj Purohit. To end this problem Dadaji calls off Dev's marriage with Radikha and fixes it with Barkha.
On the eve of Barkha and Dev's wedding Barkha lies and tells Radikha that she has told Dadaji about what happened 12 years ago and Dadaji has accepted her and will let her become Dev's wife. Radhika dresses up in Barkha's wedding outfit and takes the wedding vows.
After Dadaji realizes that Dev married Radikha instead of Barkha, he suffers a fatal heart attack. The Purohit family decides that Dev will pretend to be married to Barkha in the public eye, and Radhika will perform all of the normal tasks at home.
When Dev becomes head priest. The abbot asked him to call his wife, so he called Barkha. The crowd recognized Barkha as head priestess and so they carry on with the ceremonies. However, Barkha did not know how to carry out the ceremonial tasks, so the ceremonial priest asked if there was anyone in the crowd who had observed a fast: Radhika. Padma asked Radhika to assist Barkha with the ceremonial tasks. While Radhika was putting Dev and Barkha's hand together, Dev held her hand. It appeared as if Dev and Barkha were holding hands, but it was him and Radhika the entire time.
Meanwhile, Padma and Nanny took Radhika to the temple to offer her first meal as the new choti bahu of the family. While she and Barkha are offering the prayer, the abbot and other priests head over to the temple. Radhika quickly gives Barkha the ceremonial stole and Barkha pretends as if she were giving the prayer. She gave the abbots some kheer, and they praised her cooking skills.
Radhika returns home and performs all the duties of the choti bahu. Dev and Radhika go to the courtyard to light the sacred lamp. However, Ramanand informs the abbot that there is someone other than Barkha and Dev in the courtyard. The abbot rushes over to see if it was true; when he gets there, he finds only Barkha and Dev. When the abbot leaves, Dev questions Ramanand about who told him that someone else was in the courtyard, and he informs Dev that Maheswari told him.
Dev gets angry and confronts Maheswari about it. He and Barkha are led to the cottage room. Barkha puts sleeping powder in his juice and Dev becomes unconscious. Barkha then reveals that she loves Dev and she was the one who framed Maheswari. Radhika overhears all, and Barkha realizes that she has seen.
Barkha decides to kill Radhika and get her love from Dev. Barkha kills her by hitting her with the car twice. One day Barkha tricked Dev into putting sindoor on her forehead and since Barkha has failed to get Dev's love despite all she had done. After a month Radhika had returned but this time is different — she has become confident and fearless. This is because Kanha has disguised himself as Radhika to put an end to Barkha's crimes. Dev is now for only Radhika. The rest of the story tells how Kahna teaches Barkha the lesson she deserves.
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