Set in Mumbai in the 1970s, the film follows the tumultuous rise of power of Sultan, played by Ajay Devgan and the inevitable fall in power he undergoes when his right hand man Shoaib, played by Emraan Hashmi, betrays his trust and threatens his superiority. It is the common tale of two men who rise to power through illegal means and once they are at the top, they turn on each other to stay there. Playing love interest to the gang lord, Mumtaz, will be “Rock On!” actress Prachi Desai, while “Kites” actress Kangana Ranaut takes on the role of Rehana.

"Yes it's true that I have signed Balaji's film “Once Upon a Time in Mumbaai.”  I can't tell details about my character but it’s going to be a different character over all. I'm paired opposite Emraan Hashmi. He is one of the most successful actors and the music of all his films have always been appreciated by all. I'm hoping that even this film will also be a hit," Prachi said about the movie.

The star-studded cast alone will make this film excellent in the acting department! The deep insight to the underground world of Mumbaai is sure to be an eye-opener for a lot of people as well. The film features music by Pritam, including the tracks “Tum Jo Aaye” and “Baaburao Mast Hai.” “Once Upon a Time in Mumbaai” hits theaters on 30 July, 2010.