Crowded, hot, subject to violent swings in climate, with a government unable or unwilling to face the most vital challenges, the rich and poor increasingly living in worlds apart; for most of the world, this picture is of a possible future. For India, it is the very real present.

In this lyrical exploration of life, loss, and survival, Meera Subramanian travels in search of the ordinary people and microenterprises determined to revive India's ravaged natural world: an engineer-turned-farmer brings organic food to Indian plates; villagers resuscitate a river run dry; cook stove designers...