The songs, the spirit and the sensation of Disney's television movie "High School Musical" (both "1" and "2") set off a full-throttle show business phenomenon and transformed the lives of its young stars, like Zac Efron.
"You wake up one day and suddenly, you're just cool. I'm not different at all than I've ever been. I don't know what changed," said the 20-year-old teen icon who plays the role of Troy Bolton, a popular basketball team captain.
What hasn't changed is the talent and camaraderie of the cast, now reunited with director Kenny Ortega to shoot "High School Musical 3: Senior Year."
Chris Connelly caught up with the cast on-set getting ready to film a prom night scene.
"We have, like, a prom scene. It's actually a play that we're putting on about a prom ... I have to say we've never dressed so nice -- it almost feels out of character. But you only get to do it once," Efron said.
"So, this is my prom dress, and it's feathery; it's pink; it's rhinestone; it's fun. It's really cool," Ashley Tisdale said as she showed her dress to Connelly. The 22-year-old actress-turned-pop star plays the role of the antagonizing Sharpey Evans.
"And my favorite part about this outfit, when I turn around, it's got Danforth #8 on the back," said Corbin Bleu, a 19-year-old actor who plays Chad Danforth, a member of the East High Wildcats, and Troy's best friend.
"High School Musical 3" will be the first film in the series to open on the big screen, and it'll show its senior-year characters facing some big moments.
"Our kids are growing up. You know, we're now seniors moving into the future, together," Ortega said.
"You see the characters grow up a lot more so than ever before. You know, you have college, you have your relationships, and just trying to figure out which path to take is tough," said Vanessa Hudgens, who stars in the film as Gabriella Montez.
"Troy usually has a pretty big decision to make in every film. And in this movie, you see Troy struggling with these decisions ... whether to, you know, pursue basketball or pursue theater. And it's a pretty big one for him. It's pretty cool," Efron said.
"It's the first time that Troy and I actually get a chance to do a number together ... I'm not going to give it away. Surprise is always the best," Bleu said.
With 17 dance numbers in all, "High School Musical 3" has enough high-energy throwdowns to leave even these actors gasping for breath.
"I came into rehearsals a few weeks late -- bad idea. It was tough catching up with everybody. Corbin, who's just the most incredible natural dancer I've ever seen. I mean, Vanessa's tough to keep up with, man," Efron said.
"I'm still hurting. We're all kind of limping around," Hudgens said.
The day Connelly caught the cast on set, they had just finished 12 hours of straight dancing.
"I think I grew a full shoe size. My feet are so swollen. It's pretty bad, but it's worth it," said Monique Coleman, who plays Taylor McKessie, the leader of East High's science club.
"Well, actually, the shoes are comfortable," Tisdale said. "We had ballroom shoes on and everyone was wearing heels and everybody was like, 'Argh, my feet hurt,' and I'm like, 'Mine are great!'"
Like the earlier films, this one is not being shot on a Hollywood soundstage, but at a real high school: Salt Lake City's East High School.
Even as the last day of shooting, in late June, will be a time for bittersweet farewells, the sheer joy and exhilaration of getting to do a "High School Musical" one more time shows no sign of stopping.
"We all pump ourselves up so much. Like, before the beginning of a take, you'll see us all screaming, 'Whooo! Hooo! Yeah!' Like screaming! And we just get so pumped," Hudgens said.
"But to come back to Utah and be with my friends, it's just a dream come true. I called my mom and dad on the first day and was, like, 'I feel like I'm on vacation.' ... We really are friends and it's pretty fun," Efron said.