BERLIN (REUTERS) - Actor Ranveer Singh took nine months to get ready and is now singing the praises of Hindustani hip-hop.

And he feels India could be on the cusp of a musical revolution with the exposure from his new movie premiering at the Berlin Film Festival.

Gully Boy, directed by Zoya Akhtar, tells the tale of a student who lives in a slum and ends up temporarily substituting for his injured father as a chauffeur for a wealthy family.

He discovers a talent for rapping and uses it to vent his anger about poverty and the chasm between the rich and poor.

"This film is something that takes a genre of music that has essentially been underground in India so far and brings it to the mainstream," Singh said.

"I want this to be the beginning of something because I really think Hindustani hip-hop is a revolution. It's more than just music. It's a musical and social revolution," he added.

Singh said he grew up listening to rap music and it "feels amazing" to have recorded five songs for the film's soundtrack.

Singh, who does the rapping in the movie, said it took nine months before he felt camera-ready.

He initially wanted to become an actor to be a virtuous hero who stands up for what is right, but Akhtar had brought out a part of him on screen that was usually reserved for his friends and family.

"Zoya kind of very literally and metaphorically peels away all of those layers to kind of tap into a very real, very authentic side of me... a little bit more quiet, more reserved, more introverted and more internally feeling sensitive, vulnerable," he said.

The movie is among 400 screening at the festival, which runs until Feb 17.