The Day of the Triffids

Almost everyone on Earth has been rendered blind by the arrival of a bright comet. Bill Masen, who was unable to watch the spectacular 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: walking, carnivorous plants called "Triffids" are on the loose. (imdb)