"We have approached Shekhar Suman for the Thakur's role who rapes Bhanwari and Adhyayan for the guy who is fooled by Bhanwari. I will also be acting in the film," Tonk told IANS.
He has been associated with the small screen as creative producer of TV shows and this is his first feature film production.
Earlier, reports had suggested that Tonk was keen on casting an A-list actress for the role, but he has finalised TV actress Sara Khan.
"There was some date issue, so we felt that Sara Khan was the right choice. She has been finalised for the role," he added.
Bhanwari Devi, a low-caste woman from Bhateri village in Rajasthan, was allegedly gang raped in 1992 and the subsequent court case attracted media attention.
Tonk will focus on the controversial death of the woman and clarified that it is "not really about revenge".
The shooting will begin in December this year and will be held in different places in India and abroad.
"We will be shooting in Jaipur, Calcutta and Mumbai. We will also be shooting in Greece and Dubai," he said.
This won't be the first movie on Bhanwari Devi. In 2001, Jag Mundhra made "Bawandar " with Nandita Das in the lead role and the movie renewed people's interest in the case.
Meanwhile, the trial of the 13 accused in the Bhanwari murder case is still in progress.