Something about her airplane seatmate didn't sit right with her.
He had dark, curly hair, olive skin and a foreign accent. When she tried some small talk on the Thursday evening jaunt from Philadelphia to Syracuse, New York, he replied bluntly as though he couldn't be bothered at the moment.
She took the hint. But what was up with his scribbling on the notepad? She noticed how intensely he seemed to approach whatever it was he was working on, but she couldn't make out what his script could possibly represent. And it all added up, for her, to an unsettling feeling.
So after the plane had finished boarding, she handed a flight attendant a note, the Washington Post reported.
A half hour went by with American Airlines flight 3950 remaining on the tarmac, and the flight attendant returned to the woman and asked if she now felt okay to fly or was “too sick,” the Post said.
She said she was okay, but soon the plane was headed back to the gate where the woman was escorted off, the paper said.
Finally the captain approached that intense, dark curly haired man who had been sitting next to the woman who just deplaned — and now he was being escorted off the flight as well.
An airline agent told the man he was suspected of terrorism, the Post said — mostly because of whatever it was his former seatmate had seen him intensely scribbling (but his look and accent apparently gave her pause, too).
The man under investigation laughed, the paper said.
He wasn't scribbling in Arabic or penning code for a terrorist plot — he was in the middle of a math equation.
Guido Menzio hails from Italy and is a well-regarded economist who's an associate professor at the University of Pennsylvania.
In fact, he won the prestigious Carlo Alberto Medal in 2015, set aside for the best Italian economist under 40.
As for his scribbling, Menzio was headed to Queen's University in Ontario, Canada, where he would be lecturing about menu costs and price dispersion, the Post said, and was attempting to nail down some figures on the plane.
The Ivy League prof let those concerned see his work for themselves, and he was allowed to return to his seat, he told the Post by email, adding that the pilot seemed embarrassed. Two hours after it was set to take off, the 41-minute flight finally got off the ground.
Menzio's former seatmate never returned to the plane, and an American Airlines spokesman told the Post she initially told the flight attendant she was feeling ill — but after deplaning explained to authorities her concerns about Menzio were behind her condition.
Menzio told the paper he was “treated respectfully throughout” but is unimpressed by a “broken system that does not collect information efficiently.” He added to the Post that airline security protocol "is too rigid — in the sense that once the whistle is blown everything stops without checks – and relies on the input of people who may be completely clueless. ”
He even got a little political with the Post, noting the presidential campaign has increased xenophobia: “What might prevent an epidemic of paranoia?" Menzio wrote to the paper. "It is hard not to recognize in this incident, the ethos of [Donald] Trump’s voting base."