"I wonder how a film has entered the Indian psyche so very deeply. It had never happened before in show business," Akhtar, 65, told IANS in an exclusive interview.
"Sholay" released Aug 15, 1975, and went on to become a cult film with its mix of drama, tragedy, romance and comedy, and its characters like Gabbar, Jai, Veeru and even the one-dialogue Samba or Dhanno the mare still remembered.
"After 35 years, even the minor characters of 'Sholay' are used in advertisements, promos and films and even sitcoms revisit the film," Akhtar said.
"It's totally unprecedented all over the world. Films like 'Godfather' and 'James Bond' have created iconic characters, but their shelf life has not been so long as only a couple of characters have been remembered. I do not remember any film whose many characters are remembered after so many years."
Ironically, "Sholay", which tops the popularity chart even today, was not planned to be such a huge film.
"It was not planned to be such a huge film... We had no idea that this will become such a huge film.
"We conceived an idea and when we started working on the screenplay, it gradually dawned on us that the film has more than two important characters and, as a matter of fact, quite a few important characters so it can be a multi-starrer film.
"Honestly, when we started developing the screenplay... we didn't think on those terms. The director was happy with the script and then we decided to go 70 mm, stereophonic and so on."
"Sholay" was made on a budget of Rs.30 million and went on to become a huge success. In 1999, BBC India declared it as the "film of the millennium". Its run at the Bollywood box office even caught the attention of the Guinness Book of World Records, where it was inducted for its five-year run.
Akhtar tries to analyse the secret of the film's success.
"When something like this happens, we try to rationalise and try to find out the logic behind the success. If there's logic, then there should have been many films made of the same stature. It just happens. I am afraid there is no foolproof formula to make such a film.
"I can guess that it's the right combination of characters, right spectrum of emotions - from deep tragedy to hilarious comedies, correct combination of all kinds of feelings like love, dignity and friendship - that were fulfilled in the film."
Akhtar remembers how the film was cast. When director Ramesh Sippy was finalising the cast, Dharmendra and Hema Malini were busy with "Seeta Aur Geeta" while Amitabh Bachchan was an emerging actor.
"While developing the script, we realised we could cast big actors. Hemaji and Dharmendraji were working in 'Seeta Aur Geeta' that time and they were in the core of their relationship then.
"Amitabh Bachchan was emerging that time. When 'Sholay' cast was finalised, I think 'Zanjeer' was not released or almost released. When they were casting for the film, they had seen the trial of 'Zanjeer' and decided he was the right actor. And then one after another things happened," he said.
Everyone was sure Pran would play Thakur and was a bit surprised when Ramesh Sippy decided to take Sanjeev Kumar for the role.
Akhtar gives credit to producer G.P. Sippy for having the conviction to make the movie.
"Due credit should be given to Mr G.P Sippy. It was his immense confidence and courage that led him to make the film. People used to say 'Sippy saab to pagal ho gaye hai'; how will he recover the money? That time the film was made at Rs.3 crore and it was a big success."
Asked if he would ever try writing a script like "Sholay" again, Akhtar said: "Trying again to write something like that would be a very dangerous idea. You should try writing something that is inspiring you or you are highly interested in. But the moment you say you are writing something like that, you are in trouble because imitation of success is not a success."