This mystery blonde must have been catching her flight straight to a pool party after being filmed walking through check-in in a revealing swimsuit.

An anonymous blonde woman set social media aflame after she was filmed strolling through a US airport in nothing but a bikini — and her face mask.

An Instagram video of her runway modelling stint has garnered nearly 10,000 views in less than 24 hours.

“When you have a pool party at noon and a Spirit Airlines flight to catch at 4pm,” reads the caption to the viral clip, which was posted Thursday to “Humans of Spirit Airlines” — an Instagram account that pokes fun at passengers on the oft-lampooned American airline that is now referred to as an “ultra-low-cost carrier”.

Indeed, the shocking footage features the mystery mischief maker walking nonchalantly through the terminal of an unnamed airport while sporting skimpy olive green swimwear and toting a backpack.

However, while her itsy bitsy, teenie weenie airport attire may have left little to the imagination, she was still wearing a face mask in compliance with Federal Aviation Administration mandates, the Insta account — one of many posting the peculiar peccadillos of frequent flyers — observed.

US Transportation Security announced in August that flyers who break mask mandates can be fined from $250 to $1500.

Meanwhile, when reached by The New York Post for comment, a spokesman for Spirit Airlines said the viral video is “unverified” but not surprising given the thirsty nature of social media.

“This account often falsely attributes photos and videos to Spirit Airlines,” the rep told The Post. “The video could have been taken at any time or any place and it has no identifying characteristic of any airline. I checked, and we have no record of this on file.”

But if she were flying the airline, Spirit’s contract of carriage states that passengers may be prevented from boarding an aeroplane or even kicked off if they are “barefoot or inadequately clothed” or sport clothing that “is lewd, obscene, or offensive in nature.”

In the past, people have been penalised for much similar fashion infractions, including a Playboy model who was told she couldn’t fly on a Southwest Airlines flight while wearing her low-cut leopard print top.

It’s yet unclear if the bikini-clad bombshell had actually boarded an aeroplane — Spirit or otherwise — in that outfit.

Needless to say, her security checkpoint striptease made waves on Instagram with one commenter quipping “at least she has her mask on.”

Another viewer wrote, “If more spirit pax looked like this I’d fly on them more.”

“Security should [be a] breeze,” said another, bringing to mind another instance in which a woman donned a black bikini at Los Angeles International Airport to help expedite the screening process.

— New York Post