He is considering Sunny Leone to essay the actress on the screen, but has not approached her yet.
"I want to clarify that my film is inspired by Mamta's life, but it is not a biopic at all," Seth told IANS.
Last month, Mamta, the lead actresses of films like "Karan Arjun" and "China Gate", hogged the limelight when it was reported that she was detained in Kenya with husband Vijay Goswami. The couple has reportedly been charged with drug trafficking.
"I have almost finished my script. In fact, I started writing the script even before Mamta's news came up. The first name that struck me who can play Mamta was Sunny Leone, but I haven't approached her so far.
"I have few other names as well, let's see how things shape up. I will start shooting for the film from early 2015."
Seth claims that he knew Mamta and her family and adds that she was very ambitious.
"I knew Mamta from day one. She was so new to the industry and she used to come with her mother and sister for shoots. She was from that typical Maharashtrian family. Her life has inspired me a lot as she was very innocent, ambitious, and wanted to take short cuts.
"She worked with top stars and suddenly there was a drastic change in her life. Since 1995 we lost touch," said Seth.