Context: In 1991, the governments of the U.S. and China are on the verge of a major trade agreement, with the President of the United States due to visit China to seal the deal. The CIA learns that its asset Tom Bishop (Brad Pitt) has been captured trying to free a Briton, Elizabeth Hadley (Catherine McCormack), from a People's Liberation Army prison in Su Chou near Shanghai, China. Bishop is being questioned under torture and will be executed in 24 hours unless the U.S. government claims him. If the CIA claims Bishop as an agent, they risk jeopardizing the trade agreement. Exacerbating Bishop's situation is the fact that he was operating without permission from the Agency. Attempting to deal quickly with the situation, CIA executives call in Nathan Muir (Robert Redford), an aging mid-level case officer on his last day before retirement and the man who recruited Bishop. Although they tell Muir they simply need him to act as a "stop gap" to fill in some holes in their background files, the officials are hoping he will give them the pretext they need to justify letting Bishop die. The CIA executives are unaware that Muir had been tipped off about Bishop's capture prior to arriving at the CIA's headquarters, by fellow CIA veteran Harry Duncan (David Hemmings), for whom Bishop had been working an operation in Hong Kong before going rogue. Muir first attempts to save Bishop by leaking the story to CNN through a contact in Hong Kong, believing that public pressure would force the CIA to rescue Bishop. The tactic only stalls them, however, and is stymied when a phone call to the U.S. Federal Communications Commission from CIA Deputy Director Charles Harker (Stephen Dillane) results in CNN retracting the story. During the debriefing, Muir describes how he recruited Bishop for an operation when Bishop was a U.S. Marine scout sniper during the Vietnam War. Muir also discusses their 1976 tour of duty in Berlin, Germany, where Bishop was tasked with procuring East German assets, with Muir commanding, as well as Bishop's spy work in Beirut, Lebanon in 1985 during the War of the Camps, the latter being the last time the two saw each other. During the mission in Lebanon, Bishop met Hadley, and the two began developing romantic feelings for each other. However, it is revealed that Hadley was involved in a bombing of the Chinese embassy in Britain, causing her to flee the country. Fearing that Bishop's feelings for Hadley might compromise his cover and the mission, Muir tips off the Chinese to Hadley's location in return for freeing an arrested U.S. diplomat. Chinese agents kidnap Hadley, and Bishop cuts all ties to Muir when he discovers his involvement. After learning Hadley was the target of Bishop's rescue attempt, Muir finally realizes that he has greatly underestimated Bishop's feelings for her. Running out of time, Muir secretly creates a forged urgent operational directive from the CIA director to commence Operation Dinner Out, a rescue mission to be spearheaded by Commander Wiley's (Dale Dye) U.S. Navy SEAL team, for which Bishop had laid the groundwork as a "Plan B" for his own rescue attempt. Using US$282,000 of his life savings and a misappropriated file on Chinese coastline satellite imagery, Muir enlists Duncan's help in bribing a Chinese energy official to cut power to the prison for 30 minutes, during which time the SEAL rescue team retrieves Bishop and Hadley. Bishop, who is rescued at the end of the film 15 minutes before his scheduled execution, realizes Muir was behind his rescue when he recognizes the name of the plan to rescue him, Operation Dinner Out: a reference to a birthday gift that Bishop gave Muir while they were in Lebanon. When the CIA officials are belatedly informed of the rescue, Muir has already left the building and is seen driving off into the countryside. 
 Question: Who do CIA executives call in an attempt to quickly deal with the situation?
Output: nathan muir