Bill, who works at a farm for deadly plants called triffids, was temporarily blinded by one of them and is now in hospital. The hour approaches for the bandages over his eyes to come off, but a strange silence pervades the room.
Bill leaves the hospital to learn that everyone in the area - perhaps everyone in the world - has gone blind. He, and anyone else who didn't see the comet the previous night, are the exceptions. Meanwhile, the triffids are attacking.
Bill and his new friend Jo find a group of other sighted people, some of whom plan to form a new community in the country, but no one takes seriously Bill's warning that the triffids are a serious threat.