The legendary actor, who shot to fame with his 1969 movie "Aaradhna", ruled the film industry in the 1960s and 70s. During that time there were several reports of a woman "marrying" a photograph of the actor, kissing his car and writing him letters in blood.
In March 1973, Khanna broke millions of hearts by marrying Dimple Kapadia, who is the eldest daughter of Gujarati entrepreneur Chunnibhai Kapadia. Dimple was only 15 years old when she married Khanna.
News of their marriage shocked the entire nation and fans and media alike were curious to know why Rajesh Khanna married such a young girl.
In a documentary on Rajesh Khanna made by BBC reporter Jack Pizzey and Indian journalist and columnist Devyani Chaubal, it was revealed why Khanna married the 15-year-old girl.
When Khanna decided to get married, Devyani was the first person he had informed. According to Devyani, Khanna called her up at 3 am, saying that he fell in love with a girl that he rescued from drowning in the ocean.
"I think he was high when he called at 3 am, he sounded absolutely drunk. With 7 pegs at one party and seven pegs at another party we just don't walk in the sea like he said he did," Devyani told Pizzey.
"When I checked the news there was no such story of the waves and girl being washed away or anything. But later on by evening when I said this is what you told me in the morning, he said it happened. He just wants to believe that a wave came. When a person is drunk even a glass full of water looks like waves and storms and everything looks exaggerated. And a 15-year-old looks 30-year-old, Devyani said.
When asked why Khanna called to say that he proposed, Devyani replied saying that he called her based on a promise, which meant that whenever the actor will decide to get married, Devyani will be the first to know.
Dimple was huge fan of Khanna and frequently met him in various parties thrown in honour of his films' success. She fell in love with him and when Khanna proposed her for marriage she said 'yes'. According to reports, when Khanna met Dimple his career was going downhill, and so in a bid to regain attention from his fans the actor decided to tie the knot.
When Khanna finally got married, many people claimed that he did so for publicity and for professional reasons.
"I think he did it for the masses, he did the right thing by marrying a fair girl who is just one film old. I feel it happened because when he had made up his mind not to marry by then the girl's father had informed half the people and the girl had informed other half. So he liked what was happening to him, the congratulations and all the attention he got and fuss made over him," Devyani said.
Soon after marriage, Dimple quit films and took care of her family. But after nine years, the couple separated and filed for divorce but did not complete the proceedings.
In 1985, Dimple told India Today: "The life and happiness in our house came to an end the day I and Rajesh got married."
Despite their estranged relationship, Dimple stayed by Khanna's side in his last days and even shifted to his residence Ashirwad in Juhu to take care of him.