The film opens at a convenience store early in the morning, the present time. Juan (Gastón Pauls), a con artist, successfully scams the cashier, and later attempts the same scam again on the next shift. Marcos (Ricardo Darín), who has been observing him, steps in pretending to be a police officer and takes Juan away. As soon as they are far enough, Marcos tells Juan he is not actually a cop but a fellow con man. Juan asks Marcos to show him the ropes, because his father, also a con man, is in jail and he needs to raise money quickly to bribe a judge to reduce his father’s sentence from 10 years to 6 months.
Then, a scheme seemingly falls into their laps: Sandler (Oscar Nuñez), a former business associate of Marcos, needs his help to sell counterfeit copies he made of some rare stamps called “The Nine Queens”. The potential mark is Gandolfo (Ignasi Abadal), a rich Spaniard who is facing deportation and desperate to smuggle his wealth out of the country. Gandolfo has no time to fully check if the stamps are authentic but he hires an expert (Leo Dyzen) to do a quick check and is satisfied. He offers $450,000 for the stamps, with the exchange agreed to take place that evening. In the intervening time, the stamp expert demands from Juan and Marcos a cut, as he knew the stamps were in fact forged. The fake stamps are then stolen out of Juan and Marcos’ hands by thieves on motorcycles who, unaware of their value, toss them into a river.
To salvage the scheme, Marcos approaches Sandler’s widowed sister Berta (Elsa Berenguer), the owner of the real stamps, who agrees to sell them for $250,000. Marcos can put up $200,000 and asks Juan to contribute the remaining $50,000. Juan expresses his suspicion that he is being conned since Marcos seems to need exactly the amount that Juan has saved up; but as the $50,000 is not enough to help his father, Juan reluctantly agrees. They buy the real stamps and go to Gandolfo’s hotel, but he says he’s changed his mind and will now only buy the stamps if he also gets to sleep with Marcos’ sister Valeria (Leticia Brédice), a hotel employee. Valeria’s price is that Marcos must confess to their younger brother Federico (Tomás Fonzi) how Marcos cheated him out of their family inheritance in Italy. Gandolfo pays for the stamps with a certified check. However, the bank crashes the next morning, making the check worthless.
It appears that Juan and Marcos are both ruined. In the final scene, Juan goes to a warehouse, where he greets the motorcycle thieves, Gandolfo, Sandler and his sister Berta, and Juan’s fiancée Valeria — revealing that the real con was to swindle Marcos out of $200,000 as revenge for all the times he cheated his family and his partners.