A private plane landed in Oxford, Mississippi somewhere just before sunrise on Oct. 4, 2014.

About the same time, Michael Thompson was arriving at his office on the Ole Miss campus. A few hundred yards away, Lee Fitting was settling in for a wild day of work. Both were waiting on the prized cargo arriving around 6:30 a.m.

Not long after, Katy Perry stepped into Thompson's building.

That Katy Perry.

"I just remember thinking this is going to be the craziest day probably of my career," said Thompson, the Ole Miss senior associate AD for communications and marketing.

What followed was the dreamlike 20 hours from which this small postcard town is still recovering. When it was over, goalposts were paraded through the streets where arguably the world's biggest pop star celebrated a historic upset.

Ole Miss 23, No. 1 Alabama 17 was just part of the folklore that was Oct. 4, 2014.

It started with that early-morning flight from Dallas to northeast Mississippi.

Perry was in the midst of a U.S. concert tour that had her in Texas the night before. With the Saturday off before a Sunday show in Memphis, this was a prime opportunity for Fitting, the producer of ESPN's College GameDay.

The weekly need for a celebrity guest picker has brought a wide variety of stars to the stage of the traveling road show. Everyone from LeBron James to Lyle Lovett, Bill Murray and Stone Cold Steve Austin have held the honor previously. Perry's manager, Bradford Cobb, is a proud Ole Miss alum who had been telling Perry for years about games in Vaught-Hemingway Stadium. Thompson was the link who brought the Perry and ESPN camps together for an all-time show closer.

This was her first college football game. This was GameDay's first trip to the legendary Grove tailgating mecca. Couple that with Ole Miss' 3-0 start and a No. 11 ranking and the seeds for mayhem were planted.

Like Beatles-mania chaos.

The 10-acre shaded patch of grass was packed tighter than ever before. GameDay's set was the epicenter.

Thompson's building was Perry's initial staging ground. Arriving from the airport, she began the hair/makeup/wardrobe process. They needed her to the green room by about 10 a.m.

"By that time, people had started to figure out really where she was," Thompson said. "So when we left our office on a golf cart, it was a mob."

And they had to travel only 50 yards.

It was about that time Fitting got an idea for just how crazy things were getting outside. Police officers who stepped into the production truck told Fitting they had to shut down the surrounding streets because the crowd had grown beyond anything they'd seen.

"Then when Katy arrived playing music and we showed her arriving and the production truck was literally bouncing," Fitting said. "There were teenage girls screaming and crying and there were old men screaming and crying and there were old ladies screaming. It was a crazy, crazy scene."

Wearing a pink sweater with her hair tied tight in two red buns, Perry walked the gauntlet to the stage with mugs of hot toddies for the crew. It kicked off a prop-filled appearance in which Perry played to the partisan crowd at almost every opportunity. The boos were even muted when she picked rival Mississippi State to beat Texas A&M.

There was a corn dog for the LSU pick and a plea for then-Oklahoma quarterback Trevor Knight to call her. Thompson called her the most prepared celebrity guest in the history of the show.

The picks weren't bad either. Perry was 7-2 in the projections, though her new crush Knight lost.

"She tops the list as the most memorable celebrity picker," Fitting said without hesitation.

Ole Miss athletics photographer Joshua McCoy remembers taking one of his more memorable shots of Perry just after she left the stage.

Flanked by security guards walking through the mass of fans whipped into a frenzy, Perry's face said a lot to McCoy.

"As a photographer, I can tell when smiles are not real, but when people were chanting her name, it was just a pure enjoyment," McCoy said. "And as an entertainer, I'm not sure how much you get that. And I remember I have this picture of her and her eyes are bright and she has this smile from ear to ear."

Katy Perry leaves the set of ESPN's College GameDay on Oct. 4, 2014 before Alabama played Ole Miss.

From there, Perry wanted the complete SEC experience. Thompson accompanied her group into the Grove to visit a tent. Within 30 seconds, they were surrounded.

A while later, they were next to University Avenue to watch the band march from the grove to the stadium. The loud outfit was gone as the star turned into a fan.

"This is the coolest thing," she said to Thompson as the band went by.

That moment, among the many, stuck with Thompson.

"Here (are) our students and our band walking by and she has her phone up and she's filming it," Thompson said. "She had never been to a college football game. Her experiencing what college football is all about with the kind of pomp and circumstance of pregame and tailgating and marching bands and things that are just so unique and special to college sports and college football in the SEC ... it was neat to see somebody who's probably experienced things you and I will never experience in our life, as far as being around the world and playing in front of millions of people. For her to be in awe or mesmerized in a real fan way, it was really awesome."

Both Thompson and McCoy were struck by how genuine Perry came across all day. There were no diva moments.

This was just a California girl experiencing college football in the deepest corner of the south. All this happened before the 2:30 p.m. kickoff.

Perry sat in a few places for what turned into a wild game. Ole Miss tight end Evan Engram smiled Monday recalling that moment he realized she was in town.

"They showed her on the jumbotron about 20 times," he said Monday. "That's when I figured it out."

Ole Miss photographer Joshua McCoy got a selfie with Katy Perry on Oct. 4, 2014.

After spending the first half in a field suite, Perry moved up to the luxury boxes at halftime. The group was supposed to leave in the second half to get to Memphis.

"But she wasn't having any of that," Thompson said.

Late in the third quarter, she was ready to get closer to the action.

Watching from the field as Ole Miss took the lead for good, Perry told Thompson she would be rushing the field if the score stuck.

"Her main security guard, the look on his face was pretty priceless," Thompson said. "I think he knew he couldn't talk her out of it. He also knew that was going to be a hard deal for his job."

Of course Ole Miss held on to break a 10-year losing streak to No. 1 Alabama. Thompson promises you could see Perry sprinting to midfield in footage of the field-flooding moment. They quickly got her to the Rebels' locker room before the crowd engulfed the field and tore the goalposts from their moorings.

Photos of Perry partying across town into the night quickly traveled through the social mediums.

The Crimson Tide heads back to Oxford for the first time since that day at 2:30 p.m. CT Saturday. Again Alabama is the top-ranked team in the country.

"Hopefully she comes again," Engram said, "and brings us some good luck."

College GameDay won't be in town this time. It'll be hard to match that magical morning in the Grove. Fitting said Perry's appearance easily makes his top four shows in his 12 years with the program.

Just about everyone interviewed about that day used the word "surreal" to describe the day Katy Perry took over Oxford, Mississippi.

"You're hosting the No. 1 team in the country and Katy Perry is on GameDay," Fitting said. "You upset Alabama and the town goes crazy. I mean, it was the perfect storm. It was like it was a movie that day."