Reuben Tishkoff (Elliott Gould), in an attempt to legitimize himself in his later years, is conned by his business partner and ruthless businessman Willy Bank (Al Pacino). When Bank forces Tishkoff to sign over the ownership rights of the new hotel/casino they were building together, Reuben suffers a heart attack from the revelation and becomes bed-ridden. Danny Ocean (George Clooney), after attempting to negotiate with Bank, gathers up his partners-in-crime and plans to completely ruin Bank on the night of the opening of the casino, "The Bank", as a way to get revenge for Reuben.They decide to do so in two ways. First, they plan to prevent Bank's new hotel from winning the prestigious Five Diamond Award from the Royal Review board, which Bank has won four times before for other casinos. Saul Bloom (Carl Reiner) poses as the reviewer of the board, while the real reviewer (David Paymer), who proclaims himself to be a Very Unimportant Person, is treated poorly during his stay through Ocean's associates and the staff of the hotel on their payroll.The second plan is to rig the casino's slot machines and other gambling games to force the hotel to pay out more than $500 million in winnings; this will force Bank to cede control of the hotel to his board. Rigging of the games would require them to defeat "The Greco", a state-of-the-art artificial intelligence system that monitors the games. They plan to trick Bank into carrying a cell phone with a magnetron, created by technical expert Roman Nagel (Eddie Izzard), to disrupt the Greco. To assure that players cash out, Ocean's team acquires one of the giant drills used to bore the Channel Tunnel to simulate an earthquake under the hotel on its gala opening night.While the group prepares the rigged games, they run into problems when the drill fails. Ocean is forced to approach his nemesis Terry Benedict (Andy García) to fund the purchase of the second drill. While Benedict has a grudge against Bank and is willing to help, he only offers Ocean the funds if they also steal the four necklaces Bank has purchased to celebrate winning the Diamond Awards, now on display in a secured case at the top level of the hotel. Ocean plans for Linus Caldwell (Matt Damon) to seduce Bank's assistant, Abigail Sponder (Ellen Barkin), to gain access to the display and switch the diamonds with fake ones.As Ocean's plan proceeds on opening night, agents from the Federal Bureau of Investigation have been tipped off that machines have been rigged by Livingston Dell (Eddie Jemison), and have identified Livingston, which may reveal the rest of Ocean's gang to Bank. Basher (Don Cheadle) distracts Bank long enough to allow the gang to change the FBI records. Livingston is arrested by the lead agent, but is surprised to discover he is Linus's father, Bobby (Bob Einstein), in on Ocean's plan and there to help Linus swap the diamonds. As they exit to the roof of the hotel for extraction via helicopter, they are caught by François "The Night Fox" Toulour (Vincent Cassel), whom Benedict had ordered to intercept the diamonds. Linus hands over the diamonds to Toulour, who leaves, but discovers too late he only holds the fakes; Ocean had been aware of Toulour's presence, and arranged to extract the entire display case from the hotel with the helicopter.The remainder of Ocean's plan continues as expected, with the Greco disrupted, and guests leaving the hotel with their bountiful winnings. As Bank realizes his ruin, Ocean lets him know that they did everything for Reuben. The group uses the money they made off with to buy property north of the Las Vegas Strip for Reuben to build his own casino. As punishment for Benedict's treachery, Ocean donates his portion of the take to charity, forcing Benedict to publicly admit his philanthropy. As the group disperses on their own and considers settling down, Rusty ensures that the Very Unimportant Person is compensated by allowing him to win a $11 million jackpot at a rigged slot machine at the airport.
Output: Question: Who plans to completely ruin Bank?, Answer: Danny Ocean (George Clooney).