Filmmaker Sriram Raghavan, who is set to direct a film on the life of youngest Param Vir Chakra recipient Arun Khetarpal, says it is the most challenging subject for him.
Dinesh Vijan will be producing the biopic which is tentatively titled "Ekkis".
"Dinesh offered me this film and when I heard it, I found it interesting. 'Ekkis' is a working title. We are set in 1970s. It is the story of two eras. We have finished the script and are doing a rewrite and all," Raghavan told PTI.
"We have enough people from military on board. These things you can't get it wrong one bit. When you are working on a real story it is your responsibility to get everything right and stay as true and authentic as possible. It is all the more challenging for me as it is not my zone, I am doing something else. But I liked the story so I am doing it," he added.
Speculations were rife about Saif Ali Khan being part of the film, but Raghavan said the cast of the film is yet to be finalised.
"Whenever Saif and I meet we do talk about various subjects. We haven't spoken to any actor. All this should be announced formally."