You look at Ali Soufan, the celebrated Al-Qaeda hunter and former Special Agent of the United States' Federal Bureau of Investigation (FBI), and your first reaction is, hey, this is no Fox Mulder of the X Files television saga.
Of medium height, his black thatch thinning at the top, the words coming in a rush despite all-too-evident jet lag, he comes across as a regular guy you might have known in school.
Someone who can be trusted to share a personal secret or two about your boss, your home or your mid-life crisis.
That's perhaps why he was so good at his job.
Mr Soufan, who turns 42 in July, was such a master of the spy trade - from decoy work to interrogation and analysis - that he was responsible for sending dozens of Al-Qaeda terrorists to prison.
That helped make America, his homeland since arriving as a teenage emigre from civil war-wracked Lebanon, a safer place. Maybe the world even.
Little wonder then that within the FBI, senior officials referred to him as a "national treasure". Colleagues called him an "American hero".
His book, The Black Banners, is considered a seminal work on Al-Qaeda and the 9/11 attacks.
For the untutored public, fed on images from the Hollywood hit Zero Dark Thirty, the successful hunt for Osama bin Laden combined a mix of high-end electronics and the lowest form of torture - water-boarding suspects for information.
It is the kind of tactic that enrages Mr Soufan and violates his sense of decency and what is pro- per.
Indeed, he has repeatedly spoken against it in recent years, calling Enhanced Interrogation Techniques - or torture - ineffective, counter-productive and un-American.
How does he know?
The most fascinating character he's interrogated, Mr Soufan tells me in an 80-minute interview last week, was Nasser al Bahri, better known by his nom de guerre Abu Jandal.
At age 21, the Yemen-born, Saudi Arabia-raised Abu Jandal went to Bosnia to fight the Serbs on behalf of Muslims.
From there he moved to Somalia before, at 24, winding up in Afghanistan where he served as Osama's personal bo- dyguard.
In short, he was a treasure trove of information on Al-Qaeda and its leader.
"You meet a lot of dumb people who joined Al-Qaeda because there is nothing else to do, but Abu Jandal was very well-read, educated, even self-educated in so many ways and an ideologue too," says Mr Soufan, who now heads a global strategic advisory organisation named after himself. "And he was very opinionated, which makes it interesting. Even about internal things, about different cadres, leaders. He even had arguments with himself."
When Mr Soufan first encountered Abu Jandal in a Yemeni prison, the bearded, powerful terrorist would not even look at him.
So fearsome was Abu Jandal's reputation that prison guards had covered their faces and would not address one another by name in his presence.
The Sept 11, 2001 attacks on the US, Abu Jandal ranted, was really an operation of the Israeli Mossad - "the Sheikh (Osama) wouldn't do such a thing."
Mr Soufan noticed that Abu Jandal wouldn't touch the biscuits offered with tea, to avoid the sugar that caused his diabetes.
At their next meeting, Mr Soufan brought along sugar-free cookies, a sign of the American's concern and respect for the captive.
Abu Jandal softened and began to talk.
Soon, Mr Soufan had the identities of seven of the 9/11 bombers, enough evidence to link Al-Qaeda to the attacks.
Among other things, that evidence convinced Pakistan's then leader Pervez Mu- sharraf to make a foreign policy about-turn and support the American attacks on Afghanistan.
Osama is now dead, of course, killed in his Pakistani hideout, and much of Al-Qaeda's top rung has been decimated by America's relentless pursuit. But the terrorist threat is far from over.