What does a contestant have to do to get kicked off "American Idol"? You'd think flubbing your song so bad that you have to start over, or forgetting some lyrics, or just being kind of boring would be enough when there are only six bodies left to choose from. But on Wednesday night the contestants learned that sometimes it's one of your best performances of the season that trips you up.

One can only imagine what was going through the mind of clean-living, no R-rated-movie-watching former nanny Brooke White as she got waved to safety after becoming the first contender ever to stop a song and ask for a redo, only to watch Carly Smithson leave the show following what was arguably one of her best nights.

It was the Irish bartender's third shot at fame — her 2001 major-label debut as Carly Hennessy sold fewer than 400 copies in its first three months, and she was disqualified from "Idol" in season five because of purported visa issues — but she became the first castoff this year to leave with a smile on her face.

Maybe it was the last-minute switch from the mopey ballad "All I Ask of You," or maybe it was the too-cute T-shirt — "Simon Loves Me (This Week)" — she held up [article id="1586067"]Tuesday night[/article] after judge Simon Cowell said her rendition of mentor Andrew Lloyd Webber's "Superstar" was his favorite of the evening.

But Smithson didn't ask why she was leaving. Smiling and laughing as the remaining top five surrounded her, she faced the judges. Cowell grinned and apologized for giving his compliment, calling it a "kiss of death." After giving Smithson harsh notes throughout the season, Cowell added, "You can leave with your head held high." A relaxed, grateful-looking Smithson thanked the judges and said, "You brought us this far, and I'm very proud of myself and I'm very happy. I'm not upset that I'm going home. ... I've had the best time, I really have."

Showing her rock side, Smithson was apparently done in by a bombastic rendition of a track from "Jesus Christ Superstar," which judge Randy Jackson said wasn't her best and Paula Abdul called "unexpected." But Cowell commended her, despite the performance being a bit "shouty" at times.

Wednesday's elimination was full of shockers, as only two contestants were sent to the bottom-two stools during the course of the evening, neither of whom were expected to face the hook. Unlike past weeks, the Davids — Cook and Archuleta — were the first to make their way out on Wednesday, and [article id="1586124"]to no one's surprise[/article], they were both quickly ushered to safety. (Even last year's winner, Jordin Sparks, is predicting a [article id="1584647"]David vs. David finale[/article].) The next duo up, though, were not so lucky, as Syesha Mercado and Brooke White walked hand-in-hand to center stage, with White looking nervous and Mercado beaming, perhaps remembering her solid performance and the judge's raves about her sassy slink through "One Rock 'n' Roll Too Many."

White was asked if she would have requested a retake if given a second chance, and she said absolutely. "If I could have done it again, obviously I really wish that wouldn't have happened, but it just did. So I didn't really take time to think about it," she said. And then the shocker, White was waved to the safe zone, while a stunned Mercado tumbled to the bottom two. According to the Los Angeles Times, the often fragile White crumpled into a heap once on the couch, "lying facedown once the show went to commercial and openly weeping, a spectacle which summoned Paula to the stage to comfort her."

Last to make the long walk were Smithson and Jason Castro, with the latter slumping, his hands buried deep in his pockets and a nervous look on his face. Castro seemed ready to rehash the avalanche of bad comments that followed his mousy performance of "Memory."

"I don't really want to sing right now," Castro said sheepishly, clearly expecting to leave the show. But he got his wish, as Smithson was waved over to the stool, surprising even Cowell, who said he could not make sense of the shocking results. Admitting that at this point in the season anything can happen, the testy Brit explained White's reprieve by suggesting that her breakdown made her more "human," while Castro's performance was not very good but "charming." Jackson had a more cynical take, saying the results suggested more of a popularity contest than a singing one. Both Smithson and Mercado reprised their performances before the curtain came down on Smithson, which left Mercado and White as the only female contestants on the show.

The evening also featured a performance from Cowell-produced British star Leona Lewis (who sang her international hit "Bleeding Love"), a trip to Broadway to visit ex-"Idol" contestants Clay Aiken and Tamyra Gray at their new gigs, a bizarre animated, zombie-like Ford commercial starring the contestants and yet another primetime appearance by President George Bush, who followed up his recent "Deal or No Deal" cameo by dropping into "Idol" with First Lady Laura Bush to thank Americans for contributing to the "Idol Gives Back" charity special.

Next week Mercado, White, Archuleta, Cook and Castro will be mentored by Neil Diamond, and Wednesday night's show will feature a performance from both Diamond and Natasha Bedingfield. This year's "Idol" will be crowned on May 21.

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