The story of how Rajendra Singh brought water back to the Alwar district of Rajasthan is the stuff of legend. Singh arrived in Alwar in 1985 with the aim of setting up a clinic and providing medical services to the village community. He was soon put in place by a village elder who told him that what they needed most was water.

For centuries rural Rajasthan had enough water for domestic consumption and to keep up its robust agricultural practice. The people of the desert state managed this by conserving rain water through a system of small check dams called johads that collected water on the surface and helped recharge groundwater. Widespread deforestation changed that equation in the mid-20th century. The rains now brought silt down denuded mountain sides, which filled up the johads. With the proliferation of tube wells that reached deeper into the earth to get ground water, people stopped maintaining the johads.

By the 1980s, when Singh arrived, water was all but gone. Farming was collapsing, driving young men into cities for work, women walked for hours to get water for their households, vegetation and wildlife disappeared and rivers dried up.

Singh and other friends of his, a group that would later form the Tarun Bharat Sangh, did the simplest thing they could possibly do. They got the village elders to tell them the traditional methods of managing water in the area. They then started desilting and rebuilding a johad in Gopalpura. When the monsoon rains came, a pond formed behind the check dam and within a few months a dried-up well was recharged. The success inspired the villagers of Gopalpura to build nine more johads and slowly all the village wells were filling up with water. Even the dead Arwari river came back to life thanks to Singh's water movement.

Singh and the Tarun Bharat Sangh have been instrumental in building some 8,600 johads in more than 1,000 villages and in reviving some 6,500 square kilometers of barren land in the state. Singh has gone on to bigger battles since – saving Sariska Tiger Reserve and also being a member of the Ganga Action Plan committee till he quit it in 2012 for being a toothless body. In 2001, he was awarded the Ramon Magsaysay Award for his work.

This documentary by Earthcare traces Singh and Tarun Bharat Sangh's quest to transform Alwar from a "dark zone" where sand had replaced everything to a water-abundant region.