Varma, who is known for his hard-hitting films on Mumbai underbelly like "Satya" and "Company", announced he will be launching the first look of "Rai" today.
"#RaiMegaLaunch at 6 pm today will be biggest and costliest launch ever of film's 1st look in front of 50,000ppl with fireworks and laser shows.
"First look is of the film I am making based on the life of Underworld Don Muththappa Rai... The Greatest Gangster Ever," Varma posted on Twitter.
The "Shool" director added he is going to shoot the film in Manglore, Banglore, Mumbai, Dubai, London and Kazhakastan.
The filmmaker, meanwhile, is gearing up for the release of his upcoming film "Veerappan", which traces the life of sandalwood smuggler and bandit Veerappan. The movie will release on May 27.