The presence of Andrew Lloyd Webber on American Idol means one thing: show tunes. To create the right effect for this momentous night, the band section was extended to accommodate an orchestra and the contestants were forced to sing outside the usual Idol box. Who was able to pull it off…and who couldn’t get off the stage fast enough?

After the Top 6 Idols were introduced, the show paid homage to the composer who has meant so much to both screen and stage. For their master class with Lord Webber, the contestants were treated to a visit to the Phantom of the Opera theater. Andrew Lloyd Webber took a different approach to mentorship than last week’s Mariah Carey. He focused on the meaning behind the song and the emotional connections each singer need to make. Were they all able to follow the advice?

Before the night truly began, Randy Jackson declared “this is probably gonna be the toughest night of the season.” Simon Cowell advised that contestants should sound “memorable, but also contemporary.”

Syesha Mercado started it all off. Webber predicted that “she could well bring the house down,” and he was right. Appearing in a sexy red dress and gorgeous ‘do, Mercado belted out “One Rockin’ Road Too Many” in a truly mesmerizing performance. She began on top of the piano, enthralling onlookers with her powerful voice and very professional performance. It was, to coin a British phrase, smashing! Randy called it her “best performance to date,” while Paula agreed that Syesha “brought the house down.” Simon Cowell found her “very sexy,” thought the performance was “one of your strongest” and felt she displayed “masses of personality.” If she wasn’t the first performer up, she would definitely be safe from the bottom three. As it is…well, anything can happen on Idol.

Jason Castro made the possibly catastrophic mistake of singing “Memory,” a song I don’t think any one of them should have picked. Probably the most famous song in Webber’s extensive collection, this “Cats” classic is extremely well-known and loved by theatergoers. Castro wasn’t at all familiar with the melody. He looked great in a white suit for his performance, and his clip was absolutely delightful. With a somewhat bemused expression, Castro stared in the camera with worry in his voice, saying this tune is “kind of a popular song.” I was afraid for him right away. He did display his usual lovely vocals, putting tons of feeling into the performance. But still…it was “Memory.” Randy Jackson said it was a “little bit of a train wreck” vocally, calling it “too big of a song” for Castro. Paula Abdul disagreed with me, saying it was “wise choice” to sing that particular song. And Simon said it probably felt like the “longest two minutes” of Castro’s life. “It came over as a young guy being forced by your mum and dad to sing a song at a wedding you didn’t want to sing.” Another zinger from Cowell. “I can see that,” Randy seconded Simon’s opinion.

Next up was Brooke White, whose continued presence on the show remains one of the greatest mysteries I’ve ever known. She did nothing new - I’m beginning to think she’s incapable of doing so - and sang “You Must Love Me,” from Evita. Before she sang a note I knew the judges would fail to mention one of the more important aspects of this song - Madonna is the one who sang it in the movie, and released a single of the tune. Talk about a song for a diva - which White definitely is not. She sat on the stage wearing a dress with butterflies on it (how old are you again, Brooke?) and had to call re-do when she lost the lyric near the beginning. This is the second time Brooke’s had to stop and start a performance - though that didn’t get brought up, either. Her vocals were a bit pitchy throughout, and I remain unimpressed. “This wasn’t great,” Randy Jackson told her when it finally ended. “You need to believe what you’re singing,” he advised the contestants at large. “You must never start and stop,” Paula Abdul preached, telling her to simply “pick up the pieces” and continue. She did have one bit of praise - “you didn’t over-act.” Simon called Brooke’s do-over “dramatic,” and praised the value of live TV. But the performance? “Quite uncomfortable,” Cowell told her. “I thought it was actually a brave thing to do,” he said of Brooke’s false start. “It’s true, you never know what’s gonna happen,” Ryan Seacrest reminded the audience. No, nor who will get to hang around needlessly for weeks on end despite ever showing any variation on performance.

David Archuleta, wearing a weird outfit, was embraced by a gaggle of girls before it was his turn to take the stage. From his first note of “Think of Me,” it was another strong performance. He gave the tune much more of a pop feeling, capturing the contemporary feeling Cowell said he wanted. Archuleta did lose a few lyrics in the middle, but his big finish and amazing overall performance makes that hardly worth noting. “I knew this would be a big night for you,” Randy told him, screaming “it was the bomb!” and “this boy’s the one to beat!” You aren’t kidding. Paula called the performance “absolutely perfect.” But Simon Cowell was of a different opinion, calling it “pleasant,” but “one of your weakest performances.” Cowell felt sure Archuleta would make it through one more week, but found his stage show “forgettable.”

When Carly Smithson showed up wearing a 60s-style dress and belting out Broadway with all her heart, I was finally able to stop screaming and wondering when someone would sing “Jesus Christ Superstar.” Smithson is one of the few performers who could do this huge song justice. Offering lots of upbeat action and her usual amazing vocals, Carly completely commanded the stage. The movie version of Jesus Christ Superstar, by the way, is utterly and completely fantastic in every way. If you haven’t seen it, stop everything and go out immediately to do so. Paula Abdul gave Carly’s performance a well-deserved standing ovation, and Randy called it “definitely good.” He added, “I think the outfit’s kinda fly.” It was a good choice. “I love what you did in the chorus,” Paula told her. Simon called it a “little bit shouty in the middle,” but still found it was “one of my favorite performances of the night.” A beaming Carly then held up a T-shirt which declared “Simon Loves Me (This Week).”

David Cook closed the show, a decision I gnashed my teeth over…for about thirty seconds. He chose to sing the soft, romantic “Music of the Night,” a decision which completely irritated me until the performance began. And then, all of a sudden, everything I’ve been saying about this kid became all wrong. Cook showed a completely new side and presented a performance that was totally removed from everything he’s done on the Idol stage thus far - negating many of my complaints about him. This performance was much more Broadway, much less rowdy rock concert. With wonderful vocals, Cook showed off a huge, powerful voice and great range I had no idea he even had. Where has he been hiding this talent all this time? He completed the show with a wonderful big finish. “That was an amazing vocal performance,” Randy declared, and my teeth grit together. Damn it all, it really, really was. Now I have to stop disliking David Cook. “You are so well-rounded,” Paula told him. He is…I had no idea. She labeled the performance “fantastic,” and it was. Simon Cowell actually prefers the rock star version of Cook, but I think what David did last night was truly one of the shrewdest moves he could have made. After weeks of gravelly-voiced, sappy sad rocker affectations, David Cook suddenly become a viable performer - with great vocals. It was, without a doubt, his night.

Which leaves me with a gnawing worry. If Brooke White is too beloved to ever do wrong and Syesha can make it into the bottom three even after amazing vocal performances, with no Kristy Lee Cook to conveniently get rid of…who could possibly be next up on the elimination block?