Plot hole: After Ben loses the money and he and Mickey get into a fight, Ben talks the rest of the MIT players to risk their own money and take all of the reward instead of giving 50% of the take to Mickey. Kianna says they need at least 100 grand to play - where did they get this money from? The movie leads you to believe that Ben lost all of Mickey's money on their first night there, so they have no winnings with them. Ben's money is back in his dorm room, and you could assume the rest of them don't all have bank accounts with cash sitting in them for IRS reasons.
21 (2008)
1 plot hole - 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.
More trivia for 21
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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