Revealing mistake: When Jill gives Ben the money after the first night, you can see it is just a $100 bill wrapped around a bunch of $1 dollar bills.

21 (2008)
1 revealing mistake - chronological order
Directed by: Robert Luketic
Starring: Kevin Spacey, Kate Bosworth, Jim Sturgess, Aaron Yoo
Continuity mistake: During the scene in which Ben is introduced to the card-counting group, several members are sitting at a blackjack table. There are cards on the table in front of them. In the first shot, the cards are face up, in the next, they are face down, then they appear face up again. While no one is seen or heard dealing cards, the number of cards on the table changes in several shots.
Kianna: Everybody knows to split eights. My grandmother splits eights.
Question: If the 21 game is still played in casinos, there could be hundreds of geniuses who can count and cheat the system as shown in the film. Is this a possibility, or have casinos adopted extra security measures or something?
Answer: Yes, most casinos have now upgraded to the automated card shufflers, which constantly shuffle the cards after each deal, so there is no way that counting cards would be possible.





Answer: Casinos have always looked out for people counting cards, even before the real events that inspired this movie.
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