This film, made for Channel Four Television's Fragile Earth series, follows two American irrigation scientists who are seeking to understand the ancient Balinese irrigation system and forestall further environmental problems. Using traditional methods of cultivation, a single plot of irrigated land can produce tons of rice, year after year, century after century, with no added fertilizer and no ecological degradation. To understand why, biologist Jim Kremer takes us into the paddies with laboratory tools, showing how the rice pond becomes a miniature aquatic ecosystem which produces abundant energy for the plants, and how "development" can threaten this careful balance.

Working with anthropologist Steve Lansing, Kremer has created a computer simulation model, which shows how a system of water temples manages irrigation along two Balinese rivers. The temple system is based on the belief that all water is a gift from the Goddess of the Crater Lake. In the name of the Goddess, temple priests possess the power to settle disputes over water rights or to grant permission for a village to construct a new irrigation tunnel. With the aid of the computer model, we can easily understand how the chains of water temples form a connected system of terrace management. The priests have shown themselves to be brilliant water engineers.

Finally we return to the threat to the island's water ecology posed by modern development projects. We follow the two scientists as they present the computer to the Temple of the Lake Goddess. The interactive programme is written in the Indonesian language, and is designed to be used by the Balinese to explore the consequences of changes in their irrigation systems. A representative of the Asian Development Bank, which was initially hostile to criticism of its projects, has agreed to be interviewed as to how their thinking might change as a result of this research project. And the World Bank has now asked for assistance in developing ways to study similar systems elsewhere in the world.