At a time when most of us were fresh out of school, unable to take a wise decision about college courses, 3 Idiots became the film which on some level worked as a shield each time parents tried to convince their children the medical science, engineering, and other technical studies are not the only courses which would promise us a prospective career. 

The idea of making a film such as 3 Idiots was introduced to by Raj Kumar Hirani to Aamir Khan at a time when the superstar had inflated himself with a work out regime that required him to be strong and muscular. But director Raj Kumar Hirani wanted physical features which would require him to be lean and lanky, with wide-eyes.

Aamir Khan Rajkumar Hirani

Raj Kumar Hirani had complete trust on Aamir Khan

"Aamir...when I saw him in Ghajini he was this muscular And I wasn't...I knew as an actor Aamir was the right guy for this role but I didn't know whether physically, Aamir will look like the idiot I was looking for, I wanted a thin wide-eyed guy who looks like... a little idiotic guy, who has a mind of his own. But Aamir was very confident that he can transform from this guy to the idiot I was looking for," said Raj Kumar Hirani. 

Despite contrasting physical appearances, Raj Kumar Hirani had complete trust on Aamir Khan that he would dedicate himself for the role which he did. Aamir Khan adopted a new lifestyle to lose deflate himself from his bulky figure and started playing badminton more vigorously. 

"He stopped workouts, he got into this diet where he completely started losing his muscles. He started playing badminton very vigorously. He said that will make his face flush and make his skin tighter," said Raj Kumar Hirani in the video. 

Raj Kumar Hirani and Aamir Khan had collaborated for two projects, 3 Idiots and PK, both of which turned out to be huge hits at the box office.