For weeks, Samantha Cormode’s friends at Fairfax High School had been racking up invitations to the prom, but she hadn’t been asked.

Sam, a senior who is headed to Virginia Tech with hopes of earning a spot on the women’s soccer team, had been busy studying for finals, preparing for AP exams and making sure she stayed on top of everything she needed to do for college.

She’d been without a steady boyfriend since September, when she and last year’s boyfriend/prom date had gone their separate ways. She had opted not to go to this year’s event with a group of her friends because last year’s boyfriend/prom date would be among the revelers with his new girlfriend.

That would be too weird.

So, as the precious days of her senior year’s second semester passed at the Fairfax City high school and her classmates started buying their dresses and renting their tuxes, she began to contemplate which movie she’d be at home watching as her friends attended the biggest social event of senior year.

“I thought it wasn’t going to happen,” Sam, 17, said in an interview. “I hadn’t dated a lot this year, just a few casual dates, so I didn’t really have anybody who would have automatically asked me.”

But in this world of social media, Web sites and YouTube, asking a girl to prom has become a complicated affair. The online experts counsel high theatrics for the perfect “prom-posal.” In various how-to Web sites, the message is: the more public and original the invitation, the better.

Herein lies the tale.

Secretly, Sam had been hoping to go with David Robertson, 18, a friend she’d known since second grade who is headed to Duke in the fall. “Smart, cute and funny,” as she described him, David was a “triple threat,” the kind of guy any girl would love to hit the door with on prom night.

But day after day, David passed her in the halls with little more than a smile and hello. He seemed to have no idea that she hoped he’d pop the big question.

Little did she know, David had something big up his sleeve.

Sam had, unwittingly, set the whole thing in motion several weeks earlier when she confided to a friend that she wished David would ask her to the June 4 prom. The friend told Sam’s soccer teammate, Allison Garris, 15. Allison told David’s little brother, who passed the word on to David.

Flattered, David hatched a plan, along with best friend, Andy Lopez, 17, another senior, who had been considering asking Allison, a sophomore.

David and Andy enlisted the help of guidance counselor Erik Beall, who agreed to play his part.

Beall sent passes calling both girls out of class just before the end of fifth period one recent afternoon.

“It was pretty scary. It said, ‘COME TO GUIDANCE IMMEDIATELY.’ It was written in capital letters,” Allison recalled. “It’s never good to get called to guidance, but when it says ‘IMMEDIATELY’ in capital letters, you pretty much know you’re done.”

Allison was waiting in Beall’s office when Sam arrived.

“I was really freaking out,” Sam said. “I was like, ‘What did I do? I didn’t do anything!’ ”

Beall said in his best deadpan that he had heard some allegations about illegal activity at a party. “Your names came up,” Beall told the girls.

Sam saw her future flash before her eyes. No more Virginia Tech, no more opportunity to earn a place on the soccer team. Allison saw any opportunity to get accepted into college flying right out of the guidance office door.

Desperately, Sam pleaded her case.

“I told him, ‘I have an alibi for Saturday night! I don't even drink!’ ” Sam recalled.

Beall, stone-faced, told the girls they would have to go into another room and discuss the incident further with “some people” in there. He escorted them into the darkened guidance counselors' lounge.

They feared they were about to be confronted by everyone from their principal to the chief of police. Then, Allison heard Andy, her “half-way boyfriend,” giggle.

“I just kind of fell on the floor in the fetal position and cracked up,” Andy said. “It was soooo hilarious!”

David made his way to Sam as Andy righted himself, approached Allison and presented her with a beautiful mixed bouquet. It took her a few minutes — and a sharp slap on his shoulder — before she accepted the flowers.

David looked into Sam’s eyes and popped the question.

“Would you go to prom with me?” he asked, presenting her with a dozen roses he had picked up at Shopper’s Food Warehouse on the way to school.

“I’d love to go with you, but you are a jerk,” Sam told him, laughing.

All the planning had gone off without a hitch.

Saturday morning, Sam and her mother, Donna, headed to Tysons Corner Center to shop for a prom dress. At the third store, Jessica McClintock, she fell in love with a fuchsia “high-low,” an elegant gown of bright taffeta with a short skirt in front and an ankle-length back. She plans to wear it with silver sandals.

David will wear the tux he bought two years ago, when he first attended prom. He’s buying the tickets, and she’s offered to buy dinner. Their group will be traveling in style to the Foxchase Manor banquet facility in Manassas in a chartered bus.

Beall, who attended three proms in Illinois as a high school student, said the number of boys designing elaborate ruses increases each year.

“Some of the boys are getting pretty creative,” he said. “I am actually surprised that it’s such a big deal.”

Sam and Allison laughed about the incident Monday. Sam said David’s prom-posal put the icing on a great senior year.

That was the point, David said.

“The girls say they don't care, but they all really want to be asked in a cute way,” he said. “That’s why we do it.”