 A terrible catastrophe has struck the population of Earth. Almost everyone on the planet has been rendered blind by the arrival of a bright comet and its debris lighting up the darkened skies, but the brightness has caused permanent eye damage. Bill Masen, who was unable to watch the spectacular but deadly free firework display, finds himself in a nightmarish world where he believes himself to be the only sighted person left. But soon he finds a soul-mate, Jo Pleyton, who can also see. As the days progress, they find more and more sighted people and together they make plans to build a future. But there is a problem. A walking, carnivorous plant called a "Triffid," which up until now was kept safely in paddocks and zoos, has broken free and has discovered a taste for rotting, human flesh. The remaining blind are helpless and many fall prey to the Triffids  lethal whipping sting, but can the sighted keep this fearful plant at bay?