In his eight year long career Neil Nitin Mukesh may have played various negative characters, but the actor says the role he has in upcoming film “Wazir” is his darkest portrayal yet.Neil, who made his debut with “Johnny Gaddar”, stars in the titular role as an antagonist in the drama-thriller directed by Bejoy Nambiar.“Wazir is nothing but dark, he mocks and enjoys somebody else’s pain. This is my darkest portrayal yet. I myself was quite shocked that I played this character. He is very unpredictable. Whether it’s his face, voice or look, I had to work extremely hard for this,” Neil told PTI. The 33-year-old actor said filmmaker Vidhu Vinod Chopra, who is producing “Wazir”, was so impressed with his performance that he changed the name of the film.“When the film was offered to me, at that time it was titled ‘Ek aur Ek Do’. After I finished shooting, I got a call from Vidhu sir and he said ‘What have you done?’ I asked him if he was not happy with my performance. He said, ‘Happy? I am changing the name of my film to Wazir now.`” The film tells the story of two unusual friends – a paralysed chess grandmaster, played by megastar Amitabh Bachchan and a grief stricken ATS officer, played by Farhan Akhtar, brought together by a twist of fate.Neil said it was extremely tough to intimidate Bachchan, even though he was playing a character.“When I got to know that my character would be intimidating Bachchan sir’s character that was scary. His name is itself intimidating so getting on screen trying to intimidate him was not an easy task.