New Delhi: You must have witnessed Ranbir Kapoor's crazy journey of stepping into Sanjay Dutt's shoes for Sanju, and now, it's time to glance through how Ranbir transformed into the character of Munna Bhai for the biopic.

The makers of Sanju released a behind-the-scenes video, in which they team has meticulously documented the effort that went into the making of Munna Bhai version 2.0, AKA Ranbir Kapoor.

Apart from the amazing make-up sequences and on-set shots, there's something else that makes the video interesting - its Sanjay Dutt's reaction to Ranbir playing Munna Bhai.

In the video, director Rajkumar Hirani revealed: "When Ranbir became Munna Bhai for this film, I in my excitement showed it to Sanju and Sanju's immediate response was: 'I hope I'm doing Munna Bhai 3'." Those who have watched Sanju will agree that Sanjay Dutt's doubts are cent per cent valid.Ahead of Sanju's release, Sanjay Dutt had defended Ranbir Kapoor against Salman Khan's suggestion that Mr Dutt would have been better suited to play his older self in the biopic.

In an interview to ETimes, Sanjay Dutt said: "There is no advice for Ranbir Kapoor.

He is doing a fantasic job.

Whatever, I have seen on the sets of the movie, it is really great." Sanjay Dutt's comments arrived weeks after Salman Khan told PTI: "For Sanju, I was thinking why is somebody else playing this bit The last 8-10 years.

You cannot do justice to that.

Sanju should have played the last bit."On Sanju day, Ranbir confessed in an interview to mid-day he would often make mid-night phone calls to Sanjay Dutt to seek advice: "I would call Sanjay sir in the middle of the night, before the shoot, and ask him what he went through during a particular incident in his life."Meanwhile, in the video, Ranbir reveals why playing Munna Bhai on the big screen was a humongous challenge for him.

"Munna Bhai is one of my favourite looks and one of my favourite films.

This is amazing.

I don't think I could ever create such an iconic character.

But it feels great that there is a little part that I can emulate."Talking about transforming into Sanju and going through endless prosthetic sessions, he says in the video: "I think it must have been the 13th or I don't know ya, I lost count when we got the look right.

What's important is that when you see it on screen, the viewers shouldn't see how much we have worked on it you'll only see how it is.""The first challenge was to get the look right, which we managed.

Now we had a huge task like Mount Everest ahead of us - how to perform like Sanjay Dutt Because I was playing Munna Bhai on screen, I can't s***w that up," he added.Watch the amazing video here:Meanwhile, Sanju has been ravaging the box office since it released on June 29.

The film has made over Rs 265 crores and is inching closer to the 300 crore mark.

Sanju marks Ranbir Kapoor's first Rs 200 crore film.