<P> The film depicts the growth of the Mumbai underworld , from crime and smuggling in its early stages to its connection with international terrorism in recent times . It is believed to be based on the lives of real - life gangsters Haji Mastan and Dawood Ibrahim , portrayed by the characters Sultan and Shoaib , respectively . Originally Sanjay Dutt was chosen to play the role of Haji Mastan but the role went to Ajay Devgn instead . </P>
<P> The film depicts the growth of the Mumbai underworld , from crime and smuggling in its early stages to its connection with international terrorism in recent times . It is believed to be based on the lives of real - life gangsters Haji Mastan and Dawood Ibrahim , portrayed by the characters Sultan and Shoaib , respectively . Originally Sanjay Dutt was chosen to play the role of Haji Mastan but the role went to Ajay Devgn instead . </P>
once upon a time in mumbaai real story
once upon a time in mumbaai real story
based on the lives of real - life gangsters Haji Mastan and Dawood Ibrahim
based on the lives of real - life gangsters Haji Mastan and Dawood Ibrahim