At the start of The Drought, author J.G. Ballard introduces readers to a world that is in turmoil. Prior to the events of the novel, a ferocious drought has begun on the Earth which was caused by humans and their companies depositing toxic sludge from industrial runoff being deposited in waterways across the Earth. From there, a molecular film has developed on the surface of the oceans, which has wreaked havoc on the world. This drought has caused the oceans to recede and has caused the precipitation cycle to be destroyed. Swaths of people have been killed because of this lack of water; those who have survived struggle to survive because of the lack of water.
Ransom, the protagonist of the novel, is one of the few people to have survived the drought. An intelligent man and doctor, Ransom spends most of his life understandably trying to survive. But unlike most of the rest of the survivors, Ransom has been unwilling to follow other survivors to the receding sea.
At the start of the crisis, Ransom decided to move away from civilization and build himself a homestead. He obtains a houseboat and starts his life on a river. Eventually, the river begins to dissipate, causing an exodus from the area he lives in. In his new life, Ransom is constantly reminded of what society once was by the relics of society.
After the river disintegrated, Ransom decides that he should leave the area he is living in and go towards the ocean (specifically, the so-called "dune limbo"). Once isolated, Ransom begins to integrate himself into society—a society that has changed dramatically since he was last a part of it. Their new lives and the new social order are consumed with the need to extract water from the sea—a sea that will eventually run out of water for them to drink. But Ransom realizes that the people are fighting a hopeless battle and decides to return inland once again.
Once inland, Ransom returns to the city to see what has become of society. To his amusement, Ransom finds that people have, in fact, survived in the city despite not having much water left to drink. But the people are not normal: they are mad and resemble monsters. Their appearance and behavior, however, are appropriate given the condition of the city they are living in, something which amuses and scares Ransom.
