Varma has tentatively titled his film "26/11", and he aims to capture the "behind-the-scenes" aspects of the terror attack as well as the heroism of the officers.
"Everyone more or less has seen or heard of what happened during that time (26/11). But my attempt now would be not only to capture the physical aspect but also behind-the-scenes aspects of what exactly happened from the time Kasab and rest of the team landed on Amar Singh Solanki’s trawler in the high seas, till Kasab’s heroic capture by the late Tukaram Ombale at Girgaum Chowpatty," Varma said in a press statement.
"This will be intercut with what the various gallant police officers did in their attempt to get the situation under control," he added.
The terror attacks at prominent Mumbai locations by 10 Pakistan-based terrorists, left 166 dead, including several security personnel and foreigners, besides over 300 people injured.
Soon after the incident, Varma's walk through the half-burnt hotel accompanied by the then Maharashtra chief minister Vilasrao Deshmukh and his actor son Reitesh had led to speculations that he might make a film on the attacks.
But when he was asked if he was planning a real-life inspired movie on it, he had told IANS: "It's a figment of their (media's) imagination. I have no such plans (to make a movie on Mumbai's 26/11 terror strike)."
The filmmaker still maintains that he was not invited by Deshmukh and his son to visit the hotel so that he could see the devastation first hand and portray it realistically in a movie.
"I only got the idea now. I have enough knowledge and understanding of the events now. Also, at that point the allegations were about Riteish being a part of this project, which he is not," he said.
Varma plans to cast new faces for the movie to create a "heightened sense of reality".
He is being assisted by "Kasab: The Face Of 26/11" author Rommel Rodrigues, who has extensive knowledge of the event. However, the film will not be based on the book.
The film would be made for both national and international audiences, and Varma considers it his most challenging project.
“After my tryst with so-called the underworld films, I would consider this film as a greatest challenge of my career," he said.