Actor Kartik Aaryan says the story of "Chandu Champion" had so many twists and turns that when director Kabir Khan first narrated the film to him, he wondered if it were a true story or fictional one.

Based on the life of India's first Paralympic gold medallist Murlikant Petkar, the upcoming sports biopic will see Aaryan as "the man who refused to surrender".

The actor arrived in his hometown Gwalior on Saturday evening, along with Khan and producer Sajid Nadiadwala, to launch the trailer of "Chandu Champion".

"The first time I heard the story, the first question I asked was ‘Is it real? Did it really happen?’ or ‘Is this fictional?’ There are so many twists and turns and historical moments in his story that it was next to impossible to believe," Aaryan told reporters here.

"I was in shock when I heard the narration for the first time. But to my surprise everything was based on life instances. I was just amazed and was even sceptical for a month or so because I wanted to do it. But, I wondered if I would be able to pull it off," he added.

The trailer of "Chandu Champion" shows the titular character's journey across ages and phases, including being an Indian Army soldier, a wrestler, a boxer, a 1965 war veteran, and a swimmer. The 3.15-minute video ends with an elderly Chandu declaring that he wants to file a case of cheating against the President of India.

Aaryan, 33, said "Chandu Champion" is his "proudest" film till date which required him to undergo strenuous physical training.

“I was going to the gym daily, not having food, not doing any other film but just focusing on one picture for one and a half years. I became a robot, I became a machine and I was just following orders from them and here we are,” he recalled.

Khan, whose last directorial venture was sports drama "83", was all praise for the leading man for building his body naturally for the film.

"At times, I would wonder if this would be achieved or not because it was an impossible task. Kartik made his body naturally without any substance. For one and a half years, he didn't consume sugar. Whatever he liked to eat, it wasn’t allowed (as part of his strict regimen)" he said.

The filmmaker said he kept a check on the actor's diet even while he was shooting for the 2023 romance drama "Satyaprem Ki Katha".

"He has been a great student, we are proud of him," he added.

Khan said Aaryan was his first choice for "Chandu Champion", which he described as a "motivational" story.

"I often say it's not you who chooses the story but it's the story that chooses you. This is the story that called out to me. I said, 'It's such an inspirational story that has been hidden'.

"Up till now, no one knew about such a person and what sort of a journey he has had. This story is a must watch. I felt it is such a motivational, human story and I have to tell it. And I saw nobody but Kartik in it," said the director of films such as "Ek Tha Tiger", "Bajrangi Bhaijaan", and "Kabul Express".

Aaryan said "life has come full circle" for him as he launched the film's trailer in his hometown.

"The response that we are seeing is the effort of all the technicians, great directors like Kabir and great actors who want to prove something every day. I am grateful and hope this film becomes a success," added producer Nadiadwala.

A Nadiadwala Grandson Entertainment & Kabir Khan Films Production, "Chandu Champion" is set to hit the big screen on June 14.

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