Filmmaker Sanjay Gupta started work on his next movie "Mumbai Saga", which will focus on the connection between mill owners, the underworld and police, Wednesday.

"Today is the first working day of my New Year. Today, we begin active production on our next film 'Mumbai Saga'," Gupta posted on microblogging website Twitter Wednesday.

He has been the man behind films like "Kaante", "Musafir" and "Shootout at Wadala".