Michael J. Morell had no intention of working for the CIA. The Ohio native was fresh out of the University of Akron, where he earned a B.A. in economics. “I had every intention of going to grad school and getting a Ph.D. in economics and teaching,” he said in a 2006 interview. “But a friend of mine suggested, ‘Why don’t you send a resume to the CIA?’” He even approached his job interview as nothing more than a free trip to the nation’s capital.

Fast forward three decades, and the CIA’s top-ranking officer, David Petraeus, a highly decorated former general, has stepped down as the head of the agency, confessing to an extra-marital affair. Morell, for all of his initial lack of enthusiasm for the agency, has now been promoted from deputy to acting director of the CIA. He’s running the show.

Of course, this isn’t Morell’s first rodeo. He served as acting director once before, after Petraeus’s predecessor, Leon E. Panetta, resigned in 2011. Morell went back to his role a deputy director once Petraeus took his post.

But whereas Petraeus gained the position thanks to an impressive 37-year military career, Morell started at the bottom and worked his way up through the ranks.

His CIA career began in 1980, when he was 21-years-old. He was an economic analyst with a salary of $15,193. For 14 years, he served as an analyst and manager of East Asia intelligence, and was promoted to director of the CIA’s office of Asian, Pacific, and Latin American analysis in 1999.

He’s been in the room with the big guys for over a decade. For a time, he served as the executive assistant to former CIA director George J. Tenet, and was in charge of presidential briefings for parts of both Bill Clinton’s and George W. Bush’s presidencies. As chief of the staff that produces the president’s daily brief, his job was to sit down every morning with the president and fill him on the latest intelligence.

He was with President Bush on 9/11.

He was Bush’s intelligence advisor at the time, and, according to The Wall Street Journal, had “been at the center of nearly every fight against al Qaeda and has seen the limits of U.S. intelligence.” As such, he served as “the CIA’s devil’s advocate before the raid on Osama bin Laden’s hideout in Pakistan.”

It was Morell who in August 2001 delivered the fateful report, “Bin Laden Determined to Strike the U.S.,” that would be made infamous by the 9/11 Commission. He was in that Sarasota, Florida classroom where Bush was reading a children’s book when he first heard that the World Trade Center had been hit. When Bush asked, “Who did this?” Morell said, “I haven’t seen any intelligence, but I would bet every dollar I have that it’s al Qaeda.”

Even while Morell still served under Petraeus, agency veterans worried that he was too much of an insider to properly lead the agency.

After serving as Bush’s daily intel officer, Morell went overseas from 2003 to 2006 on an undisclosed agency assignment of which there are no details. He was named deputy director for intelligence at the National Counterterrorism Center when he returned, but only held the position for three months before he began his trajectory from the CIA’s No. 3 to its No. 2 and now acting No. 1. He was named associate deputy director of the CIA in 2006, the first person to hold that title. Two years later, he was promoted to deputy director of the CIA, the agency’s second highest in command.

And he’s managed nearly all of this with nearly no public profile.

When Petraeus took over at the CIA in 2011, it was Morell, with his three decades of agency experience, who was charged with shepherding the general into the role. Gauging the response of Petraeus’s contemporaries—both John McCain and Dianne Feinstein have publicly bemoaned his resignation and praised his tenure with the CIA—he succeeded.

Now, the man behind the curtain is alone at the top.

When it comes to how Morell might run his ship as acting director, some clues may be gleaned from the high praise he’s expressed for his former boss, Petraeus. “I’ve never seen anyone with his drive—ever,” Morell told The New York Times just last week, as Petraeus prepped to testify before Congress about the attack on the U.S. consulate in Libya. “He remembers what he asks for. Three weeks later he’ll say at a morning meeting, ‘Whatever happened to that? Is that done yet?’”

Yet even while Morell still served under Petraeus, agency veterans worried that he was too much of an insider to properly lead the agency. After all, he had never worked anywhere else. But his history with the organization and knowledge of its failures as well as its successes could prove an asset. For example, as the hunt for bin Laden peaked in 2011, it was Morell, according to Panetta, who insisted on due diligence before the raid. “Michael always raised the experience of what happened with weapons of mass destruction in Iraq,” Panetta said.

Having survived 32 years of CIA controversy and failed missions, Morell, unlike some of his more aggressive predecessors, understands the importance of humility: “We end up having bits of information that have a multitude of possible explanations,” he said in a rare 2011 interview. “You’ve got to be really humble about the business in.”

He also, presumably, understands the importance of not having an affair.