Water is set in India in the late 1930s when the practice of child marriage was still prevalent. Young girls were often wed to older men for economic reasons. When the men died, they left behind young widows who were farmed out to ashrams.

The story focalizes on one such young girl, Chuyia (Sarala) who is recently widowed at the tender age of eight. She is forced to move into a house for widows to spend the rest of her life in renunciation. As a widow, she is expected to atone for the past sins that resulted in the death of her husband.

Madhumati (Manorma), a widow in her mid-70s, is the house matriarch. By day she sits in the courtyard ordering instructions to the other widows, while at night she lies in her room, smoking ganja and listening to the latest gossip from her only friend, Gulabi (Raghubir Yadav), a eunuch and pimp.

Shakuntala (Seema Biswas) is one of the 14 widows sharing the household into which Chuyia is forced to move. Perhaps the most enigmatic of the widows, she is good-looking enough, intelligent and educated.

Quiet and reserved, Shakuntala is caught between the hopelessness of living out her remaining years as a widow and her devout adherence to the dictates of the Hindu scriptures.

Kalyani (Lisa Ray) is breathtaking, and the only widow whose hair is not shorn, as a nod to her profession which was forced upon her at an early age by the powerful head widow Madhumati. Uncomplicated and gentle, she radiates a child-like innocence.

Kalyani spends her day either playing with her puppy Kaalu, or talking to the small statue of the God Krishna she has in her room. Her nights though are surreal. Gulabi ferries her across the waters to the mansions of the rich gentry in Rawalpur. This she accepts with a quiet equanimity; it's her karma.

The rest of the widows ostracize her as they feel that close contact will result in a sullying of their purity. When she meets Narayan (John Abraham), the spiritual acceptance of her fate begins to disassemble and she becomes resistant to Madhumati's will.

Narayan, who has just finished his law degree, is an idealist and follower of Gandhi's ‘Quit India Movement.' Through pure chance Narayan meets Kalyani. There is an immediate attraction, but the restriction placed on interaction with widows makes it difficult to find a way of pursuing any kind of relationship.

Gandhi's movement is not solely dedicated to removing the British from Indian soil but also focuses on social justice particularly as it relates to the treatment of women. Narayan ignores the cultural taboos and continues to meet Kalyani in order to marry her. But marriage to widows is strictly forbidden.

What then follows will forever change their lives, and the life of little Chuyia.

Water was shot over a period of 45 days in Sri Lanka under the title "Full Moon."