Mission Critical is the eighth novel by Mark Greaney, published on February 19, 2019. It is also the eighth book in the Gray Man series. The novel centers on efforts by the main character Court Gentry to track down a mole inside the CIA and later stop a biological attack on an international conference in Scotland. It debuted at number five on the New York Times bestseller list. Plot summary Immediately after the events of Agent in Place, CIA contract agent Court Gentry is ordered home by his careerist handler Suzanne Brewer. The Agency-owned transport plane he is in makes a stop at Luxembourg to bring aboard an MI6 rendition team carrying a prisoner, a Dutch banker connected to a mole in the Agency. Upon arriving at Ternhill Airbase in England, they are attacked by a group of armed men, who kidnap the prisoner. After unsuccessfully pursuing them, Court is tasked with finding out who ordered the ambush. Brewer accelerates the mole hunt, eventually bringing in contract agent and Court's former black ops team leader Zack Hightower to intimidate the mole and reveal himself in the process. Meanwhile, former Russian foreign intelligence officer and Court's former lover Zoya Zakharova is being turned into a CIA asset in a safe house in Virginia. She is also being groomed to become part of Poison Apple, a codeword CIA program made up of singleton operatives like Gentry and Hightower. Through Brewer, she finds out the circumstances surrounding the death of her father Feodor Zakharov, a former head of Russian military intelligence, in Dagestan fifteen years ago. Convinced that he is still alive, Zoya escapes from the safe house, dispatching a group of Mexican sicarios attacking it at the same time. She travels to London to find out the truth about her father. Unbeknownst to Zoya, her father had faked his death to become a deep cover agent for the Russian government under the identity of English businessman David Mars. Bent with revenge for the supposed deaths of his wife and children by the American and British intelligence communities, he plans a biological attack on the upcoming Five Eyes conference in Scotland with the help of North Korean intelligence agent Janice Won, who specializes in biological warfare, and an agent inside the CIA, revealed as executive Marty Wheeler, providing him with classified information. Additionally, he had ordered the attacks on Ternhill and Virginia in