00 Agent

In Ian Fleming's James Bond novels and the derived films, the 00 Section of MI6 is considered the secret service's elite. A 00 (typically read "Double O" and denoted in Fleming's novels by the letters "OO" rather than the digits "00") agent holds a licence to kill in the field, at his or her discretion, to complete the mission. The novel Moonraker establishes that the section routinely has three agents concurrently; the film series, beginning with Thunderball, establishes the number of 00 agents at a minimum of 9, with the likelihood of more.

In the first novel, Casino Royale, and the 2006 film adaptation, the 00 concept is introduced and, in Bond's words, means "that you've had to kill a chap in cold blood in the course of some assignment." Bond's 00 number (007) was awarded to him because he twice killed in fulfilling assignments. (This differentiates from deadly force used by non-00 agents in the course of self-defence or offensive action; plus, in the original time frame of the novel—the early 1950s—many MI6 agents would have had recent war service.) In the second novel, Live and Let Die, the 00 number designates a past killing; not until the third novel, Moonraker, does the 00 number designate a licence to kill. Thereafter, the novels are ambiguous about whether a 00 agent's licence to kill is limited, with varying accounts in Dr. No, Goldfinger, and The Man with the Golden Gun.

Per Fleming's Moonraker, 00 agents face mandatory retirement at 45; John Gardner contradicts this in his novels, depicting a fifty-odd-year-old secret agent. Sebastian Faulks' Devil May Care features M giving Bond a choice of when to retire.

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