'X Factor' Movie Week: Top 12 turns into Top 13

• Surprise! Simon brought eliminated singer back
• The songs were supposedly all from movies
• One performance included a song from 'Mary Poppins'

The Top 12 X Factor finalists got a surprise at the start of Wednesday's show.

"We believe we made a mistake with one act," announced Simon Cowell. "We've asked this particular act to join the finals."

And just like that, the Top 12 became the Top 13 as Diamond White (who definitely deserved to be back in the competition) returned.

The show also switched from the singers being ruled by the judges to being up for public vote. Simon, along with mentors L.A. Reid, Demi Lovato and Britney Spears, offered their opinions on each act, hoping to steer and sway opinion.

This week's theme: Songs from movies.

Host Khloe Kardashian Odom got the show rolling by asking Britney who was going to perform first.

"Excuse me?" said Britney, because the audience was, as usual, screaming, chattering and hollering. (So annoying.)

Arin Ray, from her Teen Group, sang Estelle's American Boy, from the film Obsessed, starring Beyonce. With a dozen dancers behind him, he sang and rapped through the jaunty pop tune. L.A. Reid said he did a "good job." Demi Lovato said she was "a little speechless," that he "looked like a star up there." Simon praised Britney's mentoring and said Arin is "turning into a little pop star. I'm really impressed." Britney said he "owned it" and "rocked it."

Paige Thomas, from Demi's Young Adult Group, floated down from the sky in a futuristic fierce angel motif to sing Take My Breath Away from Top Gun. L.A. said she seemed "angelic" and the song was "good," but he wasn't "completely blown away." Britney liked her "theatrical" opening. Simon said he thought the track "needed to go somewhere," that there should have been something more. Demi didn't like his criticism.

Backstage interview: Khloe asks Tate Stevens, "Why are you sweating so much!?" His answer: "I'm nervous."

Vino Alan, an Over 25 competitor being mentored by L.A., belted out When A Man Loves a Woman, getting down on one knee at the end. "Love will conquer hate. East Coast, I'm with you," he said, closing the song. Britney said, "I feel ... it just really showed how unique and special your voice is." Demi called it a "phenomenal performance." Her only concern is that she has "a hard time" seeing him as a "No. 1 artist." Simon said he went from "zero to hero in one week." He told Demi it was "kind of a stupid thing you said." He cited Susan Boyle and said, "If you've got talent, you've got talent." L.A. said Vino "nailed it."

Emblem3, one of Simon's groups, mixed My Girl and Katy Perry's California Gurls as they bopped and sang and got the squeals really going. L.A. said, "I really want to be critical but ... you guys are actually perfect." Britney said they "had a lot of confidence. It was great." Demi and Simon argued about them a little. Simon said, "Every time you guys come out, it's energy and it's fun."

Beatrice Miller, 13, mentored by Britney, sang Iris by the Goo Goo Dolls, which appeared in the movie City of Angels. She was having trouble with her voice during rehearsals. She used the stage, knocked the microphone stand to the ground and powered through it. "The tone of your voice sounds like a hit record," said L.A. Demi said she was blown away by how she "pours her soul into songs." Simon said she was "not like someone who is 13." He said, "I can see you working." Britney said she has "the best personality out of anybody in this whole competition."

Jennel Garcia, from Demi's group, sang Joan Jett's I Love Rock 'n' Roll. With dry ice swirling, she pranced and danced and urged the crowd to sing with her. L.A. called it a "Joan Jett parody." Britney said, "I have one word for your performance: Hot, hot, hot." She added, "Three words." Simon said he liked her but not what "Demi has done to your look." He said she was "fun and charming," but this was "a bit of a parody." Demi interrupted him, saying he was "trying to ruin everything I've done." Simon said L.A. was right and she is "better than this." Demi pointed out that the crowd loved it.

Newsflash: On Thursday, One Direction will perform. "It's gonna be really cool," insisted Mario Lopez.

Tate Stevens, an oldster, sang a commanding rendition of Wanted Dead or Alive. Sparks flew up behind him as he crooned to an end. The crowd really went wild. Britney said, "You definitely are a true cowboy. You are a slice of America. You nailed it." Said Demi: "I love you, Tate." Simon also loved him, saying he's happy the show can give guys like him (at age 37) a break. L.A. said he hopes America votes for Stevens.

Lyric 145 put their own special, colorful rap twist on Supercalifragilisticexpialidocious from Mary Poppins, even singing it backwards at one point. L.A., smiling, said, "First of all, I hated it, but the truth is I think I'm going crazy because it was really good." He called it "inventive." Britney said, "I felt like your theatrics and everything you brought to the table was really intriguing and interesting to watch. I loved it." Demi said, "You guys got me so hyped." She said to Simon, "Who knew in that rusty old brain there were some fresh, hip thoughts." Simon praised them, saying, "You were bloody fantastic."

Diamond White, 13, explained that being sent home was "the worst day of my life." Just as she was doing a final interview, she got a call from Britney, who told her she was "too good to let go." Wearing a simple white pantsuit, she sang Whitney Houston's I Have Nothing. L.A. said it was "an ambitious song choice," but said she "brought it home." Demi said she was "trying really hard not to cry" because she was so moved by it. Simon said it was "great vocal, great song, great performance." Diamond's smile beamed. Britney said Whitney "would be proud."

Cece Frey, who loves to decorate her face and was dressed like a lion tamer, sang Eye of the Tiger from Rocky III. L.A. said the song "didn't blow" him away." Britney thought she was "like a little rebel out there. ... really courageous." Simon attacked Cece's mentor, Demi, saying the song choice "was just horrible" and had "no imagination" and offered "nothing different really from the original." Cece defended herself, saying she wanted to show she was "the fierce girl who walked into this competition," and Demi defended her, too. "I'm going to help you go in whatever direction you want to go," said Demi.

Carly Rose Sonenclar, 13, sang It Will Rain with such heart that she seemed to surprise herself, covering her mouth at the end. "That was really heartfelt," said L.A. "I loved it and I love you." Demi said, "This is you in your element. ... You're incredible." Simon agreed, saying it was a huge improvement over last week. "You could have a hit with a song like that." He said, "We're watching a star in the making." Britney said, "I feel like you should have closed the show 'cuz nobody could follow that."

Jason Brock, wearing a red jacket and surrounded by screens showing images of glowing candles, sang I Believe I Can Fly from the film Space Jam. It was more about singing than entertaining, even though L.A. likes to call Jason "Mr. Entertainment." Britney liked it but said it was "like a Vegas lounge act." Demi said it was "very cabaret." Simon said, "I like you but I don't believe you could fly. " He said he looked "like a singer in an Italian restaurant. Seriously." L.A. said, "This week, it's up to America." He told Mario, "I'm keeping my hands to myself." Instead, he put his arm around Khloe.

Fifth Harmony (the five girls previously known as Lylas and 1432) took the stage to perform from A Thousand Years from Twilight. And they showed off their ability to harmonize. "I was impressed with your singing," said L.A. "You guys shined the whole way," said Britney. Demi said they are all "powerful vocalists." Simon said, "I think there's something incredibly exciting about your potential." He could not "be more proud" of his girls.

On Thursday, we'll be right back to the Top 12 as one singer is sent home. The two who seem to be in jeopardy, judging from the mentors' comments: Cece and Jason.

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