After success of 'Dhoom' (2004) and 'Dhoom 2' (2006), there is already a buzz going around about the third edition of the series. In the upcoming instalment of 'Dhoom' factory, Aamir is playing a negative character opposite Katrina Kaif.

"I think villains have moved out of our scenarios. We don't have any villains anymore in our scripts by and large.

It's more of a social thing. At one time our society had a clear moral view. So those people were the villains in our stories too. Mill owners were the villains," said Aamir.

The actor says the profile of villains on screen has undergone a sea change over years and they are no more in-your-face baddies.

"Then it was smugglers, underworld, politicians. So society looked upon a certain section and said that we don't like these people. Today, we don't have such strong moral concepts. Being clever and opportunist is not a bad thing anymore. We don't have black and white views and moralities," he opined.

'Dhoom' series revolves around daredevil thefts, their cupid protagonists and thrilling bike chase.

Actors Abhishek Bachchan and Uday Chopra will reprise their roles as Jai and Ali in the third instalment as well.

On cultivating yet another fresh look for the action film, Aamir, who is known for going the extra mile to step into the shoes of the character he is portraying, is sporting a gymnast.

"I have been training for a year and a half for 'Dhoom 3'.

I am playing a gymnast, so I require a low body fat percentage. I have been working towards that. I have this lean and muscular look. A lot of attention has been given to the look of the film as well," the 47-year-old said.

The actor had sported a mustachioed patriot in 'Mangal Pandey: The Rising', pumped up iron to cultivate the toned physique in 'Ghajini' and again shed the six-pack abs for his role as a college youth in '3 Idiots'.