A Hindi adaptation of William Shakespeare's tragedy Hamlet, the film is set in Kashmir in the 1990s.
Touted as being the seminal performance of Kapoor's career to date, the actor explained how he approached the challenging role.
Speaking to Digital Spy, he said: "First of all I'm really glad we shot it where we shot it. Kashmir has a character all to itself. It helped the actors kind of disconnect from everything else and absorb the atmosphere and try and present it correctly. So the fact that we were in Kashmir was fantastic.
"I was surrounded by a really, really, really good cast. I had the good fortune to work with people like Tabu Maam, Irrfan sir, KK sir, and pretty much everybody else on the film. That was something that helped me a lot," he explained.
"A lot of it usually comes from the script. So spending time on the script is something which is so crucial and talking with Vishal sir, discussing various avenues of the script was very crucial.
"And beyond that it's a rather personal, lonely journey when you play a role like this, because you need to understand exactly what's going on in this guy's head. So it's instinctive and at some level you have to find your connection with the part that you're playing and that's how you kind of become the part. It's all big words but that's the attempt at least."
Bhardwaj explained why he chose Kapoor for the role, saying simply: "The character requires a younger casting. Of all the stars of his age group he is the best actor. I had to make a choice and I thought that Shahid is one of the best actors and I realized the challenges the film would have and I needed someone that I could trust and who could trust me."
Acknowledging the enormity of the role, Kapoor added: "Hamlet is a very coveted part and it's a huge complement being considered for it."
The film also stars Shraddha Kapoor, Tabu and Kay Kay Menon.
Haider is scheduled to release on October 2.
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