Dev Patel "cried" when he got the script for 'Lion'.

Dev Patel

Dev Patel

The 26-year-old actor stars as Saroo Brierley in the real life drama, a young Indian boy who is separated from his brother and mother when he ends up 1,000 miles away from his home in a Calcutta train station, and he was determined to do the movie justice as he was so moved by the tale.

He said: "I was crying when I read the script and I haven't done that before ever while I was reading something.

"You want to do justice to such a beautiful piece of work."

The movie has attracted comparisons to Dev's breakout movie, 'Slumdog Millionaire', but he insists they are "completely different".

He told Total Film magazine: "It's really easy to compare it to 'Slumdog' when you're dealing with a young boy in a situation of poverty from the beginning, but apart from that, thematically and tonally, the films are completely different.

"'Slumdog' had a kind of frenetic energy about it and a pacing, and this film is a sweeping story with these two pillars on each end, played by Priyanka [Bose] and Nicole [Kidman]."

The 26-year-old actor got to spend time with the real Saroo, but doesn't think they are very similar.

He laughed: "He's a lot cooler than me. He's beautifully smart and opportunistic.

"The fact that such a young child could survive such an ordeal... I remember being separated from my mother at a supermarket in London. I was looking at toys.

"She was there one second, I turned away and she was gone. It was five minutes, it felt like five hours. I was panicking.

"This is me in London, at home. Until that voice came on, 'Dev Patel, come to checkout number five', I was crying.

"You just imagine what this young boy went through and how long he was alone for. It's a real tale of survival."