Pull someone's leg

Origin

Picture the shadowy, bustling streets of 19th-century London, where nimble-fingered thieves often employed a crude but effective trick. One accomplice would discreetly trip an unsuspecting pedestrian, literally 'pulling their leg' from under them, while a partner seized the opportunity to snatch valuables from the disoriented victim. This physical act of tripping and diverting attention soon entered the lexicon, transforming from a literal street crime into a metaphorical jest. The phrase sheds its darker origins to describe a harmless deception, retaining the core idea of someone being playfully misled, much like those old Londoners were momentarily fooled.