"I'm a very happy, social person so this character is a complete contrast to who I'm in real life. It was very, very hard for me to become Sunny but I knew I had to prove myself as an actor. The preparation for this film was a painful process for me emotionally," Vishal said.
The actor says he prepared "really hard" for the dark character named Sunny in the film.
"I'm an actor so I approached my debut with as much honesty and integrity towards the character that I was given to play. I knew that for media and people to love my character, I will need them to hate Sunny and I prepped really hard. It was not easy because I'm not this evil person," he added.
Inspired by true crimes against women by juveniles, "Mardaani 2" sees Rani in a race against time to capture a brutal serial rapist, played by Vishal.
"To transform into Sunny, I used to put a chair in the middle of the room and I used to vent all my anger, all my aggression towards it as if it was a person. I used a rod to hit the chair, abuse at the chair, shout and scream at the chair as if I was Sunny and I had to cause pain," he said.
Vishal stressed that he was exhausted after this process because "Sunny is a person no one should ever become. Our film warns of people like him".
Talking about how he got into the skin of the character, he said: "I also decided that I will wear the same clothes that Sunny wore in the film so that he can be with me even when I wasn't rehearsing. I wore Sunny's clothes through the shooting schedule. At one point in time, I stopped taking a bath with soap because Sunny is a filthy human being."
He added: "I used to go to my house and lock myself up in my house for hours and hours and try and behave like Sunny, trying to find a body language, posture, demeanour."
Vishal searched for a lot of news clips about such criminals and in detail researched about their crimes and their state of mind while committing these crimes.
"I was in a very dark place and I remember one day I couldn't take it anymore and I broke down and kept sobbing and howling for a long time as this character ate me from inside. But, I think, everything that I did to become Sunny paid off at the end because of the love and appreciation that I'm getting now," he said.
He agrees it was a tough phase for him, but he had to go through it to bring Sunny to life.
Vishal says playing a negative character for his debut film was a tough choice for him.
"But I'm an actor at the end of the day and I would like to showcase my acting in every possible way..."
He added: "...I would love to be a part of good films and I'm not thinking about what my next film or role should be. I'm ready to do good work in good films. This is a dream come true for me so I'm not going to strategise now and just enjoy the work."
( With inputs from IANS )