"I actually felt the spit from one of them," said one onstage audience member, Haisten Willis, who was in town visiting from Georgia.

Yes, you can also see the spraying of the lead actor Jonathan Groff's saliva, the volume and regularity of which rivals the fountains at the Bellagio. On the night that this writer watched, the cascade climaxed late in the second act with the T sound line "Wendla too," which sent a huge string out from his lips and over his chin.

You could always laugh at the people in the orchestra section, who paid $80 more to sit farther away. Or just wait for the nude scene.

When I arrived at the theatre with my onstage ticket, labeled "Stage AA 10," I was directed to a hallway off to the side of the house, where an usher instructed everyone to put our belongings — such as coats, bags and cell phones — into our own personal lockers. I then walked down the aisle and onto the stage, taking my seat on the stage left side in the front row. I scanned the people around me, most of whom seemed to be in their twenties or thirties. I only glanced at the hundreds in house, which felt not unlike looking off a cliff.

The conventional interpretation of the onstage audience is that it represents the overbearing community of the 1890s German town where the musical and the original Frank Wedekind play is set, and where adults shame their teenage kids into repressing their sexuality. The show's director, Michael Mayer, says it can't be reduced to a single, clear-cut meaning.

"I don't want to tell people what it represents," he says. "It can sustain a multiplicity of readings."

Mayer had a variety of reasons for introducing the onstage seats in the show's world premiere Off-Broadway at the Atlantic Theater Company, where it began last spring before transferring to Broadway's Eugene O'Neill Theatre in the fall.

"Number one, I knew that I wanted the cast onstage all the time," he says, so he added spaces for the cast to sit. "And then I realized, when they're all onstage in scenes, then all the seats will be empty and we'll lose the sense of people watching the play." So he added onstage seats for audience members, and had the cast sit among them when not performing.

He also noted that at the Atlantic, some seats at the back of the house were taken up by a sound mixer, so it was a bonus to have some extra real estate. On Broadway he found himself with more standbys, so he turned the four of them into ensemble members by having them perform from the onstage seats. They begin by sitting camouflaged in modern dress, but they eventually stand up and join in.

Mayer does say that it's important for all audience members — onstage and in the house, the main part of the audience — to see that other people are watching the show.

"If you're in Jersey Boys, you can forget that you're in an audience. You can get sucked up into the story," Mayer says, but with Spring Awakening, "you're constantly aware that you're watching something" because you see the other people watching as well.

Audience members have breached the fourth wall on Broadway before. Tom Hulce, a producer of Spring Awakening, made his Broadway debut in Equus, which had audience members onstage, as did the musical Cats and Michael Frayn's play Copenhagen. Ayn Rand's Night of January 16, which began on Broadway in 1935, plucks audience members to serve as jurors for a trial, and currently The 25th Annual Putnam County Spelling Bee picks a few of them to try to spell words like "casserole." In Off-Broadway shows such as Tony 'n Tina's Wedding and De La Guarda, all audience members are in the action, as the stage and the house are one and the same.

Mayer noted that European nobles used to have the privilege of sitting onstage, but the practice ended in the seventeenth century. Onstage seating for Spring Awakening turns that tradition on its head, since it's "for the hoi polloi, not the royalty," he points out, as seats are only $31.50.

Before the show began, the usher walked onstage and told everyone not to bring food or drinks up onstage after intermission, and that we'd get our Playbills from her after the show.

Kimberly Grigsby, the show's musical director — who also sits onstage every night with the band to conduct and plays piano and harmonium — says that the onstage audience's self-consciousness and lack of personal items guard them from the typical distractions. Normally, as a conductor standing right in front of the first row, she is accustomed to hearing whispering, fidgeting, ruffling and the jiggling of Junior Mints. But it doesn’t happen onstage at Spring Awakening.

"They behave themselves," she says. "There's no talking. They're not flipping through their programs to read. They're actually paying attention to the show. I don't even catch people's eyes wandering."

The four onstage ensemble members arrive with the rest of the audience. Each one grabs a ticket from the prop table backstage and then at around 7:55 PM they sneak out a door that opens into the house (on the right side, if you're facing the stage) but is shielded by a curtain.

Sometimes, when they walk onstage "we act like we came together and we act disappointed that we're not sitting together," says Krysta Rodriguez, who's in the ensemble.

When one of them has to perform, his or her spot is taken by one of the two standbys for the adult roles (who usually stay backstage).

A little into the first act, the ensemble suddenly pop up and begin singing.

"When we stand up — oh my goodness, some people freak out," she adds. "We had one kid who could barely sit in his seat he was so excited."

As Ryan Boring, another audience member in town from Georgia, said after the show, "The guy scared the crap out of me."

The most anticipated part of the onstage experience — the sex scene at the end of the first act — turned out to be no big deal. From my perspective in the front row of the stage left side, peaking over Groff's shoulder, I got a peak at Lea Michele's chest and a lot of Groff's behind. But the experience probably wasn't as erotic as seeing it from the house, where the audience gets a full view of the two of them horizontal.

"I find they react more to the masturbation scene than to the sex scene," Grigsby observes, which would make sense, as the act, which Jonathan B. Wright performs while seated and facing the audience during the song "My Junk," is easy to see from the side, and comes suddenly, early in the show.

Still, Michael Hojlo — who's a manager at the restaurant 7 Square next door and who has seen the show both onstage and from the house — said of the sex scene, "It was more exciting being closer. The further away you got you kind of missed those nuances," such as facial expressions.

At intermission you can schmooze with ensemble. I struck up a conversation with Robert Hager, an ensemble member sitting next to me. Understandably, he said he enjoyed participating in the show every night, instead of sitting backstage waiting for an actor to be absent. "It makes it a lot easier" to learn all the roles, he said, "and a lot more fun."

"They always want to talk to us: 'You totally fooled us, you had tickets and everything!'" Rodriguez says of the audience. "Or they get really scared of us. They realize that now people will be looking in their direction, and they get really self-conscious. They always ask, 'Are we going to have to do anything? Are there going to be lights on us?' People ask if they're dressed properly. When there's a spotlight on the person next to them, they get really uncomfortable."

Also during intermission, I asked Eric Lane, a fellow onstage audience member, whether he had felt the audience's eyes on him. He replied, chuckling, "I wasn't thinking of that until now. I was just so engaged with what was going on that that just kind of went out of my head."

Certain parts are better onstage than others. "The ones where they're jumping around or they're moving," such as "The Bitch of Living," work better onstage, observes Hojlo. "The ones where they don't do as well onstage are the duets, where they're very much more focused toward the audience."

"You're behind the action some of the time — you're going to miss certain words and lyrics and some of the finer points," Mayer says, of the onstage seats, "but hopefully the tradeoff is that you get a dynamic experience."

Mayer says that there are speakers on the floor below the seats, aimed at the onstage audience. But the sound from the speakers aimed into the house is sometimes more powerful and creates a bit of an echo to those onstage. "The sound is a little bit off," Hojlo acknowledges. The benefit is that you sometimes hear the music directly — from the mouths of the singers, or from the instruments, which are a joy to watch up close.

"If you're out in the house, you're hearing a mix — you're hearing all of the voices coming out of the same speaker," Grigsby says. "But when you're onstage, you're going to hear it from the source."

So far, no audience member has tackled an actor in mid-scene or rushed to the piano and started playing chopsticks. Some fanatics will sing along, Mayer says. Others — or perhaps the same ones —will offer a hand to shake or say "good job" when an actor sits down nearby after a song, Rodriguez says.

Christine Estabrook, one of the adult actors, is allergic to cologne, so some very nice-smelling audience members have had to be moved at intermission.

"I've kicked people a couple times, I'm not going to lie," says Rodriguez. "There's a part where I have to swing my leg over, and depending on how large or small the person next to me is, I kick them — in the leg."

Grigsby says that after the show, even audience members who weren't onstage feel comfortable marching up the steps to talk to her. "They don't come to the edge of the stage and say 'Excuse me,'" she says. "They come right up onstage to talk about the music or talk about the lights. Which is great."

The reason for their brazenness, Grigsby thinks, is that because of the onstage seating, the entire audience — onstage and in the house — feels invited into the world of the musical. "There's not a barrier — we're up here telling the story and you're down there listening," she says. "We're all a part of this world, and your participation is necessary."

It acknowledges, she says, that "every single one of us can tell a part of this story. We all go through this. We all become adults."

As Hilary Paige Willis, a drama student who sat onstage, said afterwards, "When you sit that close, you feel like part of the story."