(CNN) Saroo Brierley's search for his birth mother is a story about unwavering determination against incredible odds, the strength of the human spirit and one man's faith in the capabilities of Google Earth.

Brierley was 5 years old when he was separated from his older brother one night while at a train station in rural India.

Brierley's older brother had left him sleeping on a bench, but when he returned, Brierley -- then known as Sheru -- was gone.

Young Sheru had awoken from his nap and boarded a train in search of his older brother. His day-long journey landed him more than 700 miles east of his home, in a place where he didn't speak the language.

He'd later learn he'd ended up in Calcutta.

For weeks, he lived on the streets, escaping a bevy of dangers. Eventually, he was taken in at an orphanage and adopted by a couple in Australia, after officials failed to locate his family and hometown.

Since Sheru did not know how to spell his name, Brierley ended up going by an incorrectly spelled version -- "Saroo."

Saroo Brierley and actor Dev Patel arrive at the AFI FEST 2016 Presented By Audi for a screening of The Weinstein Company's "Lion" at TCL Chinese 6 Theatres on November 11, 2016 in Hollywood, California.

Twenty years later, Brierley decided to launch a search for the mother, siblings and home he remembered only in fuzzy childhood memories. To do this, he decided to retrace his steps using Google Earth.

Those who don't know the rest of the story soon will. (Warning: Some movie spoilers follow below.)

Brierley's journey to find his family in India is the subject for The Weinstein Co's "Lion," a movie due out November 25 that is a likely Oscar contender.

But when he started his quest, Brierley said the possibilities -- the interest in his story, his subsequent book and the film starring Dev Patel that now tells his tale -- were the farthest thing from his mind.

"I was just so high on hope and so determined to find what I'd been sort of yearning for for some time and defuse the weight off my shoulders," Brierley told CNN in a recent interview.

Brierley has now seen "Lion" a few times, he said. And even though he lived the experience, he said the film was a "roller coaster of emotions."

"I tried to suppress my tears but I couldn't," he said. "It was just so hard to."

He wasn't the only one. Brierley said his Australian mother Sue, played in the film by Nicole Kidman, was "enchanted" by the movie.

"She was speechless at some times, to the point where she grabbed my leg and almost dug her nails into it," Brierley said, laughing.

Brierley's warm relationship with his adoptive mother is one of many emotional drivers in the movie. And though some parts of the movie were "heightened" for storytelling purposes, Brierley said it was important to him and the filmmakers that the characters be portrayed authentically.

Nicole Kidman and Sunny Pawar in a scene from "Lion."

He was especially pleased with one key scene between Patel and Kidman, in which they talk about her motivation for adopting him as a boy.

"The way that was acted out was just so organic and pure," he said.

There's one key opinion Brierley is still waiting to get -- that of his birth mother, Fatima Bi Munshi.

He said they're working on getting the movie translated into her native Hindi, as she does not read. Though he's recounted his experience to her before, he thinks the movie will put the journey into a greater perspective.

"I think it's going to give her a shock as in, 'Whoa, I didn't realize that this is actually what happened,'" he said.

CNN's Sara Sidner visited Brierley's mother back in 2012, shortly after the two had been reunited.

Then, she recounted the disappearance of her son and spoke about the devastating second loss she experienced the same year. Brierley's oldest brother, who had accompanied him that fateful night, was killed a month after Brierley went missing.

"I would go to sleep at night and my mind would wander in madness," she said. "I didn't feel like eating. I kept looking out for him on the streets, asking people about his whereabouts. I found him nowhere. It was a very difficult time."

Brighter days have fallen upon the once fractured family.

Brierley said he's been back to India about 14 times since they were reunited, in part thanks to the trips he's taken as a result of the interest in the story of their reunion.

"It's worked pretty well and I'm so touched and humbled about everything — that things like this can happen," Brierley said. "I wish there were more stories like this."

He's working to make that happen.

Brierley said he hopes to get into script writing, with a focus on penning films that lift people's spirits. He wants them to walk into the theater "thinking about things that are going to change their minds in a positive way [or] ... who they are as humans."

Brierley's life has undoubtedly changed as a result of what started as an against-the-odds quest. And though the ultimate result came with some sadness, he said at the end of the day, "that's just life."

"I guess this was my destiny," he said.

CNN's Sara Sidner contributed to this report.