It opened in Australian cinemas (including Greater Union in Wollongong and Shellharbour) on Thursday May 16. It tells the true and tragic story of a Christian missionary and his family who were helping Indian residents with leprosy.

Emily, Campbell and Isaac Ellis play Staines' children in the film, which was shot in 2012.

Now the trio are aged 17, 14 and 12, and said it was a little surreal to watch the finished product so many years later.

Even mum Pippa had a double take when watching the trailer, thinking their voices had been dubbed.

"When I saw I thought, my kids don't sound like that - but they did at the time," she laughed.

While the kids didn't realise just how famous the leading actor was.

"At first I actually didn't know who [Stephen Baldwin] was," Isaac said. "Because I was so little I had no idea ... but now I look back and I feel really lucky that I actually got to work with him."

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He and his brother Campbell both said they loved the experience, and how different it was to how they thought movies were made.

"You have to take a lot of shots, like lots and lots of them," Isaac said. "We had to spend a lot of time doing one scene but I used to think it was one straight scene and then you're done."

The Ellis family were living in India at the time, with the children often being cast for modelling jobs. After returning to Australia Mrs Ellis said her children did try and pursue modelling and acting but it has fallen by the wayside.

The Least of These: The Graham Staines Story is currently in selected cinemas.

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As the social fabric of life in rural India disintegrates in the late 1990s, journalist Manav Banerjee (Sharman Joshi) moves with his pregnant wife to the State of Orissa in hope of a better life and the promise of a lucrative career.

When speculation mounts that local Australian missionary Graham Staines (Stephen Baldwin) is illegally proselytising leprosy patients, Manav agrees to investigate undercover for the newspaper. What he finds is a series of revelations that are difficult to fathom and even harder to explain, and Manav is forced to make a choice between his own ambition and the truth.

In the end, his actions spark a tragic event that is felt around the world. Based on a true story and shot on location in India, "THE LEAST OF THESE" beautifully illustrates the power of love, hope and forgiveness to overcome hate.