This movie is inspired on a true story; in fact, it is based on a best seller titled “Bring Down the House”, written by Ben Mezrich, which was inspired on the true story of a blackjack team from MIT that trained to become experts card counters to win millions playing blackjack at casinos all around the world.

However, neither the book nor the movie, reflect the true story as it really was. There are many things that did not happen as shown in the movie; and it is understandable, since sometimes it is necessary to add certain moments and characters to the plot to make it more interesting. So, let’s leave the book and the true story aside, to concentrate in the movie.

“21” narrates the story of a MIT professor, Micky Rosa, who gathers a team of the most gifted students, in order to teach them and train them in the art of counting cards. He recruits a new member to join them; Ben Campbell, a shy and extremely clever student who needs to find a way to pay college tuition. After being approached by Micky, he realizes that the solution to his money problems is in the gambling industry, playing cards.

This team travels to Las Vegas every weekend to play blackjack at different casinos. We must consider that the original team in real life took place in the early 90s, and back then top sites to play online blackjack for real money didn’t exist; therefore, they had to travel to every casino they could around the world.

Getting back to the plot, the team travels to Las Vegas with false identities to play at blackjack tables and win lots of money.

The team was guided by Micky Rosa, a math professor, who teaches these students his mastered tactics, making them go through different tests. They develop a secret language, to communicate with each other while playing at the same table. They use a specific strategy based on counting cards.

Nowadays, you can find online blackjack strategy in the blink of an eye; it is only a click away, since the internet is full of different strategies and charts of all kinds to help you understand how to improve your game and chances.

But, back then, having access to this kind of information wasn’t that easy or obvious. Moreover, applying a complex strategy on a land-based casino is not as easy as it is when you play live blackjack online.

Micky Rosa, has the experience and intelligence to understand the probabilities and odds of blackjack when playing by strategy and card counting. He trains the six team members in order to win as much money as they can at every blackjack table possible, using a special technique: “the spotter and big player strategy”. The spotter is the one in charge of counting cards, and must signal the big player (with the proper code word) to increase the bet when the count is favorable.

The spotter must keep a low profile, bet small, and play by basic strategy; when the big player sits on the table, the spotter plays for a few more minutes and then leaves. This is a very well-known and successful card counting strategy, which was quite used some decades ago before the real online blackjack era began.

Ben comes to enjoy this extravagant lifestyle; he becomes a big player. One of the members (Fisher) becomes jealous and fights with him causing his expulsion from the team. At this point the security of the casino has begun to keep an eye on Ben.

On the next trip to Vegas, Ben is emotionally distracted and loses $200,000 at a game, for not leaving the table when he was signaled. This causes Micky to quit the team, but the rest of the team decides to go on. However, they finally get caught by the casino’s security, and Ben gets beat up.

After that Micky steals Ben´s winnings and prevents his graduation. The other members of the team convince Micky to take a last trip to Vegas, as part of a plan to avenge Ben.
The team wins $640,000 until they are spotted by the security (Williams), making Micky run off with a bag of chips that are fake. Williams was part of the plan, and ends up capturing and beating Micky, while Ben is allowed to play one last game enjoying immunity, but, when Ben is leaving with his winnings, Williams betrays him and takes all the money at gunpoint.

However, Ben and his long-time friends make another team which makes a lot of money.