Three-card monte

Three-card monte, also known as find the lady and three-card trick, is a confidence game in which victims, called marks, are persuaded to bet money that they can pick the money card from three face-down playing cards. It closely resembles the shell game except that cards replace the shells. In its full form it is a classic short-con in which a shill pretends to conspire with the mark against the dealer while actually working with the dealer, so the mark has no real chance of winning at any point, and anyone seen winning is presumed to be a shill. The swindle was already in use by the turn of the fifteenth century.