Adapted from the non-fiction book A Long Way Home by Saroo Brierley, Lion is about a five-year-old Indian boy who, after a wrong train takes him thousands of miles away from home and family, survives many challenges before being adopted by an Australian couple. Twenty-five years later, armed with only the scantest of clues, he learns of a new technology called Google Earth, and sets out to find his lost family.

Lion is out in cinemas from Friday.