The shell game (also known as Thimblerig, Three shells and a pea, the old army game) is portrayed as a gambling game, but in reality, when a wager for money is made, it is a confidence trick used to perpetrate fraud. In confidence trick slang, this famous swindle is referred to as a short-con because it is quick and easy to pull off.
When an individual not familiar with the shell game encounters a game on the streets, it appears that bets are being placed by numerous players, when in reality, most of the persons standing around a game are in league with the operator in a confidence ring. Shell game gangs generally prefer to swindle one "player" (victim or mark), at a time. The apparent players actually serve various roles in the swindle: they act as lookouts for the police; they also serve as "muscle" to intimidate marks who become unruly and some are shills, whose job is to pretend to play the game, and entice the mark into betting. Once a mark enters the circle of apparent players and faces the operator, the gang surrounds them to discourage an easy exit and to keep other pedestrians from entering and disrupting the confidence trick gang's action on the main mark. The job of crowding around also protects the operator from any incriminating photographs being taken of the act. The operator and the shills will try to get the mark into a heightened state of anger or greed. Once this is accomplished, one shill will pretend to disclose a winning strategy to the mark. It is all a ruse to get the mark to place a large bet.
The operator's trick is sleight of hand. A skilled operator can remove a pea from under any shell (or shells) and place it (or not) under any shell (or shells) undetected by a mark. So it is never of any benefit for the mark to watch the movement of either the shells or the operator's hands.
When the operator has finished moving the shells around, he asks the mark if they wish to bet on the play. If a mark agrees, they have to place their money down before they can point to a shell. Using sleight of hand, the pea is revealed to be under a different shell than chosen.
If no mark wants to play, one of the shills may start the play in order to animate the mark. The shill will either lift a shell which is "obviously" wrong and will lose his money, or he lifts the "obvious" shell and wins. Or he may pretend that he has discovered some trick, and either "succeed" or clumsily fail.
The game should not be mistaken for an honest game. It is not possible for a mark to win, even if they know how the trick is worked, or even if they "accidentally" pick the shell that actually has the pea under it. Through very skilled sleight of hand, the operator can easily hide the pea, without the mark seeing. Any player who is suspected of understanding the trick, or does not place a bet and just wants to watch, will be quickly edged away from the table by the shills or the muscle. The shell game set-up and lay-out is quick and simple, so that in the event of trouble, or if they are signaled that authorities are approaching, they can remove all traces of the game in seconds.
The shell game has been played at least since the Middle Ages, as evidenced by several paintings of that time. A book published in England in 1670 (Hull Elections - Richard Perry and his fiddler wife) mentions the thimblerig game. In the 1790s, it was called "thimblerig" as it was originally played using sewing thimbles. Later, walnut shells were used, and today the use of bottle caps is very common.
It was believed to be introduced to the U.S. by a Dr. Bennett, who became famous (or infamous) for his skill at the game. The swindle became very popular throughout the nineteenth century, and games were often set up in or around traveling fairs. Fear of jail kept these shell men traveling from one town to the next, never staying in one place very long. One of the most infamous confidence men of the nineteenth century, Jefferson Randolph Smith, known as Soapy Smith, led organized gangs of shell men throughout the mid-western States, and later in Alaska.
Today, the game is still being played for money in many major cities around the world, usually at locations with a high tourist concentration (for example: New York and Los Angeles, in the United States, Rambla in Barcelona, Spain Gran Via in Madrid, Kurfürstendamm in Berlin, Germany, Bahnhofsviertel in Frankfurt am Main). The swindle is classified as a confidence trick game, and illegal to play for money, in most countries.