Britney Spears has a posse. In every corner of the world there are diehard Britney fans, choreographing routines to her songs, analyzing her public persona on social media -- and of course, showing up with passion, sass and costumes for her live performances.

The Britney diehards were out in full-force on Sunday at Circuit of the Americas: While Formula One cars sped around the track, several camped out all day -- with lawn chairs -- just to be in the front row for the iconic singer. I spotted more styles of Britney apparel than I ever thought possible: T-shirts from every tour, hats boasting her iconic slogans “Work, Bitch” and “It’s Britney, Bitch,” sweatshirts with her face on them and replications of several different Britney music videos looks.

The Sunday show at COTA was a big moment for me -- although I was tantalizing close to attending a Britney Spears concert when I was in third grade and she was my absolute favorite singer, I had never seen her live before.

Talk of the performer’s concerts always involves eager mentions of the fact that she lip syncs during all of her shows, and indeed, as soon as the clock struck 6 p.m. and the backup dancers paraded across the stage, Britney’s pre-recorded vocals for “Work Bitch” came blasting through as the singer opened the show.

FUNK AND FIREWORKS: Bruno Mars warms up the COTA crowd

But if you love -- or even like -- Britney Spears and go to her concert, you know she doesn’t sing live. And Britney knows you know it, too. She mouths the words, but she’s not overly caught up in appearing to deliver an authentic vocal performance. What she is focused on is putting on a show.

And she did. Britney brought her signature mix of inherent naivete and scandalous not-that-innocence to the COTA crowd with a dizzying, sparkling Vegas-inspired show that cartwheeled through her nearly two decades of hits and played right to the forever fans.

Decked out in a variety of strappy, glitzy lingerie-adjacent costumes, she tackled her early singles early, providing dark and Halloweenish takes on "...Baby One More Time" and "Oops! ... I Did It Again,” and charged through a playfully naughty set of mid-career tracks like “Gimme More” and “Do You Wanna Come Over,” accompanied by her sweaty, muscular backup dancers -- men and women.

That’s one delightful thing about the Britney-verse of the stage: There is an air of raunchy flirtation in everything -- Britney can still writhe-dance like the best of them -- but the physicality is all well-meaning, sexually fluid and collaborative, done with a wink. Sexy but safe.

Take for example “Freakshow,” when Britney announced with a strangely British accent that she was going to pull an audience member onstage to dance. It turns out the singer and her backup dancers needed the audience member to dress up in leather straps and collar, for Britney -- wielding leash and crop -- to walk around stage like a dog. Very BDSM, very kinky, but everyone onstage was grinning and having a ball.

Other notable moments included a dance break for a medley of Missy Elliott tracks, which I didn’t understand but did very much enjoy, followed by a remix of “I’m a Slave 4 U” that sampled Migos’ “Walk It Talk It.” The creepy off-kilter circus theme for “Circus” was particularly fun and well-executed, and the final four songs of the night -- “Toxic” before “Stronger” before “(You Drive Me) Crazy” before an ebullient “Dance Until the World Ends” that ended with confetti -- felt like one giant party.

One thing that made the Britney Spears show so fascinating is that you can see all the mechanics at work. Every movement, costume and facial expression is exaggerated. The breaks between songs for costume changes are not subtle. And when Britney does each dance move, she clearly reveals a practiced familiarity and also an underlying understanding of the intention behind it. It’s like you can watch it on her face as she thinks “now I do this, because …”

As my friend said, “it’s like her mom is in the audience mouthing ‘smile!’” Her mom, her fans, the world, what’s the difference?

Each time Britney adjusted her ponytail or poofed her bun mid-dance move, every time she skipped across stage smiling, she communicated that her No. 1 goal is to do a good job. And it’s impossible not to love her for that.