Marcus Stevens had a revelation when he traveled to Sacramento to take in a performance of "Forever Plaid."

"I had done the show for a year and a half the first time and then '[Plaid] Tidings,' but I'd never seen it. And I was laughing out loud. I knew all the jokes that were coming. I was so caught off guard, I was just totally caught up in it."

Now he has an inkling of why those die-hard fans keep coming back night after night. "Plaid" castmate Joe Domencic says, "We had one lady, Barbara, who's no longer with us, she came and saw the show over 50 times."

"Forever Plaid," which opened the CLO Cabaret five years ago, begins a return engagement tonight. During its 200 performances in 2004, some fans became regulars as they fell under the spell of the four doomed members of a '50s boy band that miraculously gets a second chance to realize a dream.

It's not just Pittsburgh that loves these guys: The musical has played for Plaid Heads worldwide since it opened in 1990. A 20th anniversary special, with narration by David Hyde Pierce, was filmed this summer for a planned DVD release.

Stage manager and understudy Mark Turner, who was a back-up in '04, was in the Sacramento production of the musical before returning to the CLO Cabaret with Chris Crouch (Frankie) and J.D. Daw (Jinx).

"We actually got cards congratulating us on our opening -- from people in Pittsburgh," Turner said.

"That's awesome!" said the Plaids who remained behind, Stevens and Domencic, who are reprising their roles as Sparky and Smudge.

"When we came back for 'Plaid Tidings' [in 2007] it was like family welcoming you home," Stevens says of local audiences. "There was kind of this amazing feeling from the audience of like, 'Oh God, I know that guy. He's the guy with the glasses; he's the guy with the retainer.' Pittsburgh audiences are very responsive that way."

"I think there's going to be a reunion like that for a lot of people," Domencic says.

These Plaids are staging a mini-reunion of their own, including Guy Stroman, who directed the first run of the musical here. Stroman is the original Frankie from the show's off-Broadway debut in 1990 and has staged several long-running productions.

Last week, Stroman and the quintet of players pulled chairs into a circle in the CLO Academy of Musical Theater and took time from rehearsal to talk about the joys and challenges of being a Plaid.

Like the teen buddies they play onstage, the camaraderie was evident in their easy banter:

Stevens: "I think my favorite thing about 'Plaid' is that it's just this hour and a half of joy, this little departure into laughing and great music and these guys who are just like the nicest people you're ever going to meet. And people have responded to me about that. People have said, 'It just makes me feel good.' And we haven't had a lot of theater like that recently. ... It makes you feel good in a really smart way. ..."

Crouch: "It is, and it's uplifting on top of all that. And wholesome."

Turner: "I think it's also a different style of comedy that people aren't used to listening to anymore. Especially with modern-day theater, things have just gotten so edgy and crass and rude ..."

Stroman: "There's no irony in this at all."

Turner: "... I think the word wholesome is such a great way to say it. You feel like you're watching 'Leave It to Beaver' again. You're not laughing at dirty words. It's the situation."

Well, Turner does admit that one of his favorite moments "is when Marcus shakes his butt." Everyone, even Stevens, has to agree that's a fun moment. And Turner gets chills when the spotlight hits Daw for the first strains of "Cry."

They exchange stories about bringing audience members onstage for a piano duet of "Heart and Soul" or as a Perry Como stand-in. And then there are the times when, despite knowing every twist and turn that "Forever Plaid" has to offer, they just crack each other up.

In case you've somehow missed it: The Stuart Ross show takes place on a night when the stars align for four high school chums to come back after they've been killed in a car crash, while on the way to their first big gig -- at a hotel lounge. A little thunder and lightning, and suddenly they are onstage, granted their wish to perform the concert of their dreams.

Finding the right blend of personalities and voices is the key to charming a "Plaid" audience.

"You don't get to sing this way much anymore," Stroman explains. "This is not doo wop, it's not barber shop ... It was a very specific time period of vocal music that didn't really last all that long because all of a sudden those vocal harmonies started going into rock 'n' roll."

He credits arranger James Raitt with putting together "smart, intricate jazz-based harmonies" of standards such as "Three Coins in a Fountain," "Crazy 'Bout You Baby" and the closing number, "Love Is a Many Splendored Thing."

Daw says those last few chords of "Splendored" are among his favorite things about the show, while the director points out that Daw is that unusual theater person who "actually likes Saturday matinees. It's unfathomable."

While Daw has had a long run as Jinx, Crouch is finding his voice for his debut as Frankie.

"Quite honestly, it feels like I'm walking in Vaseline right now," he says. He's confident, though, because of the experience and warmth in that inner circle -- like the feeling that Sparky, Smudge, Jinx and Frankie project from the stage night after night.

"What makes it universal for me, what makes it ageless, timeless, is their relationships," Crouch says. "I feel like what brings them back has as much to do with how badly they want to do the show as it has with how much they love each other. When it's done well, when it's done honestly, I think that comes across in a powerful way. I think that's something for people to latch onto."

Doug Oster writes a blog, "Growing With Doug," exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.