It’s ironic that Ranbir Kapoor is all set to play the title role in a biopic based on Sanjay Dutt, considering that the Khalnayak star once wanted to beat up his father — veteran actor Rishi Kapoor.Strange as it may sound, this is exactly what’s written in Rishi’s biography ‘Khullam Khulla’. “It’s true. Sanju was having an affair with Tina Munim at the time, and he thought that Chintu (as Rishi is referred to by his friends) was having one with her too. Sanju and I were like brothers, and he told me one day, ‘We have to go to Chintu’s house and beat him up’. We went to do that, but his fiancée Neetuji managed to convince us that Chintu was not in any such relationship. So we left,” discloses fellow actor Gulshan Grover candidly.Back then, Rishi was yet to marry Neetu Singh. As Rishi is known for his outspoken nature and tweets, his book is expected to have more interesting revelations of the kind. Now, it’s up to Ranbir to make peace with an old story.