Welcome to the high school a cappella thunderdome.

Cherry Hill East High School's a cappella group, Stay Tuned, will be featured on Pitch Slapped, Lifetime's new reality show about the cutthroat world of singing sans instruments.

Pitch Slapped premieres at 10 p.m. Tuesday.

The show is set up as a classic underdog story, with Stay Tuned taking on the juggernaut Highland Voices team of Northern Highlands Regional High School in Allendale, N.J. In preparation for the Summer Invitational, each team is coached by an expert from the a cappella world.

Think of it as the Super Bowl if everyone showed up for the halftime show.

Stay Tuned is supposed to be the "ragtag, Bad News Bears a cappella group," according to their celeb coach, Deke Sharon, who is referred as the "Godfather of a Cappella."

Sharon has quite the resumé for an a cappella pro. Most recently, he has been vocal producer for the Pitch Perfect movies, the second of which came out this summer, grossing a whopping $184 million at the box office.

In Sharon's Bad News Bears metaphor, Highland Voices is, of course, the Yankees. Stay Tuned has competed against Highland Voices at the International Competition of High School A Cappella. And for the last five years, the local Davids fell to the North Jersey Goliaths.

Cherry Hill and Allendale are pretty far apart, and the supposed epic rivalry between the two schools would seem manufactured for cameras. But distance does not matter all that much in the small world of high school a cappella.

"We would spend the year building up our set" for the international, said Megan McCance, 18, a former Stay Tuned member now studying cosmetology. "It made it all so nerve-wracking. We had this goal of beating this one group."

Perhaps the members of Stay Tuned are not the ragtag underdogs Lifetime has portrayed them to be. Heather Lockart, choral director at Cherry Hill East, had heard of the show when producers were casting around for school teams, but she didn't apply. She directs all vocal music programs at the school and did not think she could handle any more on her plate. Producers found out about Stay Tuned from other New Jersey high school groups, who cited it as their biggest competition.

"If you look at [Stay Tuned], it's a United Colors of Benetton ad," Sharon said. "There's economic diversity and racial diversity. Everything about this group summarizes what a cappella is at its best, which is this group coming together and finding this commonality."

In the show, Sharon takes on Stay Tuned while Broadway vet Diana Preisler coaches Highland Voices.

"The fact of the matter is [Stay Tuned are] not a group of superstars. They don't have this ready-for-Broadway lead singer, but the great thing about a cappella is the sum is better than the individual parts. I was finding songs and arranging to let them find their best selves, and learn the techniques of a cappella," Sharon said.

"They were very choral," he said. "They were about standing and delivering the song. But with a cappella, your eyes have to be engaged and your heart has to be there with the lyric. I had to get them to connect with the music, and they have to connect with their hearts. That was the first big step for them."

Sharon taught them how to move and connect with the audience.

Stay Tuned may not have been used to the ramped-up rehearsal schedule - they used to practice only once a week after school - but they were used to guest teachers. Lockart said she wasn't precious about handing over the reigns to Sharon. She said she was relatively new to a cappella when she started working at Cherry Hill East and regularly brought in guests - including former members of rival teams - who could teach the kids what she couldn't, like beat boxing.

Lockart was less concerned about who was leading her a cappella team than about how her kids would be portrayed on camera. "Ultimately, [producers] picked out some dramatic things and spent more time on them than I would feel comfortable with, but they portrayed things very accurately," Lockart said.

Despite a need for the dramatic in reality TV, a cappella is inherently about community, about voices coming together. Much of the humor is derived from Pitch Perfect and Glee, those pop-culture entities that put a cappella in the spotlight, finding humor and warmth in the union created by blending voices.

"Building harmony with other voices is just euphoric," McCance said. "There's something about it that makes you feel like you're a part of something bigger."

Pitch Slapped 10 p.m. Tuesday on Lifetime.