After the bombing of the subway station near Wall Street, the alarms went off in Federal Reserve Building and cops and excavation crews surrounded the blast site. A few minutes later, Simon and his men entered the building posing as businessmen. Simon is under the name "Mr. Vanderfloog" when he went in the bank. After the alarms finally went off, they were met by the corporate stockbroker. Then they took out the stockbroker and the Federal Reserve Marshals in the lobby. Then some of the henchman, including Karl, removed their blazer jackets and now disguised themselves as security guards at the bank.
Then some of the men disguised as maintenance workers, including Nils and Klaus, surrounded some Federal Reserve Deputy Marshals. Then Simon and his men stood back from the security guard as the guard in the security office fired warning shots at them. Then Katya entered the bank's gold storage vault through the weak wall that tore open by a drilling vehicle. As the guard called the front desk to get the police down here, it was revealed to be one of Simon's men. As the guard kept firing his shotgun to keep Simon and the men at bay, Katya kills the guard with a long, curved knife and kept doing it until Simon put a stop to it.As the men proceed in the gold storage vault, Karl was awed by the sight of the gold bullions in the vault and he called it Fort Knox. However, Simon scoffs and says that Fort Knox is for "tourists". Then contract terrorist Mathias Targo calls in the loader, which it rammed through the one of the security gates and pulled the other ones open to steal the bullions. Simon says the vault is 10 times more than Kentucky and throws a gold bullion to Karl to show how heavy it was. They loaded the gold to 14 dump trucks they stole earlier.
As New York detective John McClane and shopkeeper Zeus Carver returned to Wall Street, one of Simon's men Ivan warns Simon, who is en route to New York City Water Tunnel No. 3. Simon calls Karl and tells that McClane is heading to the Federal Reserve and to kill him. As McClane entered the area, Karl bluffs McClane that there is nothing unusual except for the bombing near them. Karl leads him to the vault elevator where Otto, who is posing a police detective, and two other henchmen, Kurt and Berndt, posing as Federal Reserve Marshals. Once they got in the elevator, Simon's men surround McClane acting like nothing's wrong. But McClane sees Otto's badge and recognizes the badge number of his colleague and friend Ricky Walsh. He realizes the men he's with are imposters and kills all of them.
Zeus got to the bomb sight while McClane gets off the elevator. McClane finds Ricky's body in the subway stairway near the hole where they drilled through to get to the gold vault and realizes that Simon is not out for revenge, but to heist gold from the Federal Reserve Bank. He and Zeus leave the building to try to stop them from getting away.
- The Federal Reserve Bank on Wikipedia