A sign in a crowded station says beware of pickpockets, and nearly everyone who reads it pats the pocket where the wallet sits. That reflex tells every thief in the room exactly where to reach. This episode treats pickpocketing as a study in human attention. In the transit hubs of Rome and Barcelona, teams use lurching trains, dropped maps, blocked walkways, and doorway crushes to overload the senses, because a brain flooded with touch cannot isolate one hand sliding into a jacket. The trick needs about three seconds of hijacked focus.

The story then moves back to the 17th and 18th centuries, when pockets were separate pouches tied at the waist and a cutpurse needed only a sharp blade. Records from the Old Bailey in London show female pickpockets far outnumbering men, most of them working in private rooms rather than crowded streets. British law made the crime a hanging offense from 1565 if the goods were worth more than 12 pennies, yet its own loopholes and the prejudices of juries let most defendants escape the gallows.

• Henri Kassagi, the illusionist who advised on Robert Bresson’s 1959 film Pickpocket, worked by one rule: a larger motion always covers a smaller one.
• At the 2015 Frieze Art Fair in New York, an artist hired a pickpocket to slip small sculptures into visitors’ bags.
• A conviction required proof that the victim noticed nothing, so a thief caught in the act could not be found guilty of pickpocketing.
• After a 1782 precedent, drunk victims were held partly responsible. Only 6 percent of defendants were hanged, and 61 percent of women were acquitted.
• George Barrington, the Prince of Pickpockets, dressed like an aristocrat and robbed dukes and earls at galas and theaters while the London press followed his trials.