Katie McCabe wasn’t nervous.

“One more minute?” she asked excitedly. “Is that him?”

McCabe held her violin in her hand and craned her neck to look up the stairs. She stood in the lobby at Portland’s Deering High School with four members of her band – two guitarists, a bassist and a singer. Students crowded around – their cellphones at the ready – waiting for the sixth band member.

Elliott Weeks, the drummer, was in class on the second floor. Any minute, his teacher would send him to the main office. Weeks didn’t know he was really walking into an elaborate “promposal.” McCabe was waiting at the bottom of the stairs to invite him to the annual dance, but she wasn’t going to just walk up and ask.

“Why not go all out once in front of everyone?” McCabe said beforehand. “I’m a senior. I can just graduate the embarrassment away.”

The Deering High School prom is scheduled for Saturday at the Marriott at Sable Oaks in South Portland. The event is open to juniors and seniors and their dates, so sophomores like Weeks aren’t allowed to attend unless they go with upperclassmen. Though Weeks and McCabe are in different grades, they have known each other since middle school. When McCabe and four other seniors formed a band this past winter, they asked Weeks to be their drummer.

“Our name is TBD,” McCabe said. “Our rule is that every time someone asks what it stands for, we have to come up with something different. So let’s see, today our band is called Tyrannosaurus Box Dumplings.”

IT WAS TIME TO EXECUTE THE PLAN

When the rest of the band starting making plans for the prom, Weeks wanted to join.

“He said, ‘Hey you should take me. I want to go, and I don’t have a date,’” McCabe said. “So I said sure.” McCabe certainly isn’t shy. She is a competitive tap dancer, a camp counselor and a natural public speaker. She decided to do something flashy to formally invite her friend to the prom.

She thought about corny invitations – a box of candy with a note about how sweet prom would be. She remembered last year when someone wrote “PROM?” in chalk on the school patio. At least four other people pretended it had been their idea and used the message to ask their dates. She wanted to do something even bigger.

Weeks had been nagging the band to learn the Dexys Midnight Runners song “Come On Eileen,” so McCabe rewrote the lyrics to swap “Eileen” with “Elliott.” The rest of the band learned the song on the sly during free periods at school. McCabe conspired with one of Weeks’ teachers. Last Thursday, less than two weeks from the prom, the time came to execute their plan.

The final period of the day had just begun.

Minus Weeks, the band met in a soundproof studio in the music room at Deering. They had time for a couple of practice runs.

“We don’t have anything to lose,” McCabe said.

“You have a prom date to lose,” joked Spencer Todd, one of the guitarists.

Singer Helen Bellafiore reread the lyrics on her cellphone. Todd high-fived Caroline Hodson, the other guitarist, after their first run-through. Bassist Jade Bucha planned to hold a white board with the words, “Prom?” McCabe did a little dance of excitement as they practiced. At 2 p.m., TBD took it from the top one more time, and then they were ready.

They split up as they filed out of the music room.

“2:25, main lobby, be there,” Bellafiore shouted at a group of students in the hallway.

Bellafiore and Bucha ran to the library to print out the lyrics. Todd and Hodson went to set up their guitars in the main lobby. McCabe ran to a first-floor classroom to borrow a dry-erase marker for the white board.

“Will you go tell Mr. Adams to send Elliott to the office at 2:25 p.m.?” she asked another student.

The girl ran up the stairs, and McCabe raced to meet the band near the front door to the school.

“Good luck, Katie,” someone shouted.

A crowd gathered in the main lobby. Teachers in the nearest classrooms allowed their students to empty into the hallway. They opened Snapchat on their phones.

From the stairs came the faint sound of footsteps, and then a cheer went up.

Weeks had arrived.

‘YOU’RE A SOPHOMORE, BUT MY AGE IS MORE’

Weeks laughed when he saw the other members of TBD and dropped his backpack to the ground.

McCabe grinned and brought the bow to her violin to play the song’s opening chords. The guitarists began to strum.

“Come on, Elliott,” the band sang. “Come on, Elliott.”

Bellafiore launched into the lyrics.

“Poor old Elliott,” she sang. “Sounded sad upon the mention of prom, thought he’d go solo all along. Oh, his mother cried, she’d bought him a suit so who could blame her.”

The crowd grew as the music drew people from their classrooms. Students walking in the front door stopped to listen. Bellafiore hit the chorus.

“Come on, Elliott, oh I swear, what we mean, at this moment, you mean … everything,” she sang. “Kate in that dress, her thoughts I confess, verge on flirty, come on Elliott.”

At the music slowed, McCabe put down her violin. The crowd cheered. She swayed to the music and pointed at Elliott.

“You’re a sophomore, but my age is more,” McCabe sang. “So I’m askin’ you, come on, Elliott.”

In the background, Bellafiore chimed in.

“Come on, Elliott, go to prom,” she sang.

Students began to dance and wave their phones in the air as TBD played the final verse. Weeks laughed, and when the final notes died away, he joined the raucous applause.

Megan Doyle can be contacted at 791-6327 or at:

mdoyle@pressherald.com

Twitter: megan_e_doyle

Correction: This story was revised at 8:50 a.m., May 12, 2017, to reflect the correct spelling of Katie McCabe’s name. An earlier version of the story spelled her name incorrectly.