Analysis of information sources in references of the Wikipedia article "Pigeon drop" in English language version.
As the movie opens, Roy and Frank are playing a sophisticated form of the Pigeon Drop, in which victims are convinced they have a tax refund coming, and then visited by Frank and Roy themselves, posing as federal agents who want cooperation in catching the tax frauds.
The offender then left the victim and the victim opened the bag and it only contained shredded paper, and no money.
Here is the start of a pigeon-drop scam from 'House of Games.'
Then there the ring dropping trick, by which a dupe is induced to buy a worthless ring, but purporting to be a diamond, by a man who pretends to find it just in front of the dupe, but alleges he has neither time nor inclination to seek a better market.
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