Donal MacIntyre's journey with water begins in Bergen, the wettest place in Europe, where he finds how to live with almost constant rain. He follows the rainwater into the icy northern seas where it joins the greatest ocean current of them all. Rising in the Indian ocean, it fuels the mighty Indian monsoon, bringing inches of rain crashing to the ground in seconds. To find out how the perfect raindrop is formed, Donal paraglides into the heart of a monsoon rain cloud. In Texas he discovers the secret of rainmaking, before experiencing the terror of a flash flood.