Updated

Empty pizza boxes and Pepsi cans litter the floor of Miami's Fillmore Theater as weary contestants struggle to keep their eyes open and voices on pitch. It's Day 3 of "The X Factor"'s second-season boot camp — and it's also a reboot camp for the Fox reality competition, which struggled to find its voice after being imported from the U.K. last September.

A new panel of judges enters the theater and takes their seats: acerbic Brit and "X Factor" creator Simon Cowell, global pop superstar Britney Spears, former Disney star Demi Lovato and record exec L.A. Reid. Even with new table mates, Cowell is still the same old Simon. "Arguably one of the worst things I've ever heard," he tells a group of dejected boys after their performance. "Shambles. It was a joke."

Cowell and Lovato banter like brother and sister, but Spears remains relatively quiet until an energetic rendition of Vanilla Ice's "Ice Ice Baby" gets her moving and elicits heaps of praise. "You guys were so good, I wanted to cry!" she gushes. "I wanted to jump on the stage with you."

And when a panic attack freezes another young boy, Cowell calls "Cut!" consults with producers and heads backstage with Reid to give a pep talk. "We had a word with him," Cowell tells the other members of the boy's group. "Give it 10 or 15 minutes and make it feel like there's no pressure." When the singer returns, the judges are pleased and Cowell and Spears high-five.

The judges have reason to celebrate now that they're finding their groove following a
tumultuous off season. After winner Melanie Amaro was crowned last December, Cowell canned judges Paula Abdul and Nicole Scherzinger, as well as host Steve Jones. With the additions of Lovato, 20, and Spears, 30, Cowell is emphasizing a more youthful tone, made most evident by changing last year's over-thirties category to singers 25 and up, to compete with the groups and two more categories still to be determined.

"We have to make this event television," insists Cowell as the quartet gather backstage to discuss the show's new faces, format changes and their heavyweight competition this fall.

TV Guide Magazine: What was missing last season that you've fixed with this new panel?
Cowell: I think there was too much history with me and Paula. I adore her...but it just felt like that relationship was too steeped in American Idol history. With these shows, you can never be complacent. Whenever we choose a panel, you've got to be interesting and you've got to know what a star is.
Reid: I think Simon really nailed it. In the time that I've spent with both Britney and Demi, I'm impressed with their ability to really identify greatness and talent.

TV Guide Magazine: Britney, what was your reaction when Simon offered you the job?
Spears: He was absolutely adorable on the phone, and he is so sweet. My makeup artist used to do his makeup, and we were joking around about me doing it. So I guess it was one of those meant-to-be things.

TV Guide Magazine: And Demi, what was behind your decision to join?
Lovato: I really feel like being the first young judge on any of these vocal competition shows is a lot of pressure, but at the same time, it's great because I get to bring in a perspective from the audience that's around my age. I was nervous at first because it's not like I have the experience that L.A., Simon and Britney have. But I know how hard people have to work to get to where they want to be, and I can spot somebody who has talent and who's memorable and could be a pop star.
Spears: She's a very good judge.
Lovato: Thank you! I'm tough and I'm fair.
Spears: She toughens me up! Sometimes I listen to you and I'm like, "Oh, God, I've got to be a little stronger."
Cowell: There have been many times when L.A. and I have been the nice, sweet ones.
Lovato: We've done so much to get here. If you want to get here, you've got to put in the work. So I think that's why I'm a little tougher and why Britney's a little tougher. We don't give the horrific metaphors that Simon gives.
Cowell: You think it, though.
Lovato: I think it, but I will not say it.
Reid: That's the Simon magic. He says it and everybody's thinking, "Yeah, that's exactly what I was thinking, but I just couldn't have said it that way."

TV Guide Magazine: What do you think viewers will be surprised to learn about you?
Lovato: I've said from Day 1, when [Britney] stepped on set, how funny she is. I don't think a lot of people have gotten to see her personality and her sense of humor.
Spears: The same about Demi. Even though she's really young, she has such a sophistication about her. She's cooler than me.
Lovato: No, I'm not! Oh, my God!
Cowell: It's quite difficult sometimes when you've got singers judging other singers, because they can be selfish. And I've watched this very carefully; these two want to find a star.

TV Guide Magazine: If "The X Factor" was around when you were both starting your careers, would you have auditioned?
Spears: Absolutely.
Lovato: And she would have won!
Cowell: I couldn't imagine trying to mentor these two. "Can you do this?" "No." "Will you listen to me?" "No."
Lovato: We would fight, totally. Actually, I think that when I was a little younger, I would just have taken it from Simon. And now, he's a coworker and he's fun. Actually, you're my boss, you're not a coworker.
Cowell: Yeah, you're my boss now!

For more with "The X Factor" judges, pick up this week's issue of TV Guide Magazine on newsstands Thursday, August 23!

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