On 5 December 1952, as Londoners rushed around the city after the start of the festive season, fingers of fog began to unfurl between chimneys. But as night rolled in. the fog thickened, and soon a blanket of smog was choking the capital. Londoners stumbled around the streets, unable to see further than a few metres in front of them.
When the Sun rose the next day, it failed to blaze away the smog - instead, it grew thicker and