Photo: James Minchin/FX

Last week, Douglas Laux, a former CIA agent who spent eight years undercover — including a stint in Afghanistan — hosted a Reddit AMA in which he fielded questions about his time as a spy, his life since leaving the agency (“Now I’m just a cat owner with a PlayStation who likes to drink Capri Sun”), and how he managed to keep such a big secret for as long as he did.

Laux, who recently published a memoir titled Left of Boom, told his family and everyone else that he was a low-level salesman (“and since that’s pretty boring, there truthfully weren’t a lot of other follow-up questions”). Keeping his cover wasn’t quite as drama-filled as it was for the Jennings, the KGB agents living as a suburban Virginia family in The Americans (a show produced by another former CIA officer) – much of the current season deals with the fallout after the married spies decide to reveal their true identities to their daughter – but he still made some missteps. When he learned he was headed to Afghanistan, he told his parents he was moving to Hawaii — a place so far away from their Midwestern home, he assumed, that they’d never try to come visit him.

Incidentally, he was wrong. They tried, a few times. And that wasn’t the only snag he hit while trying to guard his secret:

Those closest to me always were suspicious. And those closest to me were always my girlfriends. They always thought I was cheating on them or in the mafia or selling drugs or something illicit. Which they would constantly point out but I just had to suck it up and deal with it. I talk about in my book how my girlfriend once found my Agency badge in my sock drawer (cool secret hiding spot huh?) and how I had to talk my way out of that disaster. Didn’t go over so well.

“My social life was robust,” he explained in another answer, “but do understand that came with a lot of stress that I brought upon myself. Consider, every new person I met was one more person I had to keep my secret from and weave another lie with.” Ultimately, Laux was able to compartmentalize — “I do not regret that my life was a fabricated lie,” he said, “because it was only my job that I was hiding from everyone.”

Not everyone can handle this sort of secrecy as well as Laux did. In fact, the stress of constantly lying can lead some law-enforcement agents to emerge from undercover assignments with deep psychological scars. A 2006 paper in the Journal of Police and Criminal Psychology, for example, explained the mental toll that a double life can take: “Psychologically, the essence of all undercover operations is the same,” it reads. Officers “knowingly and purposefully develop relationships that they will eventually betray” with both the people they’re targeting and the people they meet in the context of their assumed identities. “Many undercover officers find this dual betrayal a difficult road to walk, adding to the stressors already inherent in undercover work.”

But beyond this paper, researchers’ knowledge of spy psychology — both what makes someone suited to the job in the first place and what the long-term effects of being a spy are — is fairly limited. That’s partly because it’s such a hard thing to study. A 2014 paper in the Intelligencer, the journal of the Association of Former Intelligence Officers, pointed out that plenty of information about spies is classified by intelligence agencies that want to protect their methods. And then there’s the problem of sample size: There just aren’t many current or former spies out there who can be corralled into submitting themselves for study.

Still, more general research on lying can shed some light on how some people effectively pull off fictional identities for so long. In 2014, a team of Dutch researchers compiled a list of 18 traits that make someone an effective liar. Some are fairly straightforward, like confidence, preparedness, and quick thinking. Others are slightly less intuitive — one item on the list, for example, was “unverifiable responding,” or knowing when to say “I don’t know” to a question versus making up an answer that could later be debunked. Another was “eloquence,” or the ability to give answers so long and so winding that the questioner becomes confused.

And Laux, who lived a lie for the better part of a decade, had something else working in his favor. One of the other traits on the list was experience: The more you lie, the better at it you become.