Falling asleep on a train during the journey with his brother cost Saroo Brierley dearly for 25 years. The five year old boy was lost in Calcutta for over a week and was later adopted by an Australian family. Saroo grew up with a large map of India posted on his bedroom wall and, upon his graduation in 2011, he decided to use Google Earth, the digital online map that covers all the places on earth, to find his way back home by tracing the memories that he could still recall. He calculated the hours it would take for travelling from Calcutta to all the surrounding towns and cities and searched for the landmarks and signs that he still remembered. Incredibly, as he zoomed in on Khandwa town, he saw the waterfall that he had visited as a little boy. From there he continue his exploration until he finally found his way back to his original home and family.