On Wednesday night's "X Factor," the auditions were over and boot camp got underway. The emotions were running high as 120 contestants headed to Miami and moved one step closer to the crown. But, before any of them took the stage, judge Simon Cowell had this warning: "This will not be a holiday. This will be the most intense week of their lives. You're looking for killers."

And some killed their songs in the best way, while others murdered their tracks in the worst possible way.

Throwing Down the Gauntlet
L.A. native Diamond White, 13, explained that there's "nothing big enough to explain what this [opportunity] means." And, she kicked off the night with a version of Whitney Houston's "I Have Nothing" that was full of gravitas years ahead of her tweendom. The judges did like her, but noted that they may have just been overly dazzled by her since she was the first to perform at boot camp.

Not So Total Recall
Jessica Espinoza did share that she was "so nervous" before she decided to take on Mariah Carey's "When You Believe," so it may explain why she struggled through the track when she did get in front of the judges. "I am pretty disappointed," Demi Lovato said after she wrapped up, adding she was nothing like she remembered during the auditions.

Miss Independent
Jennell Garcia, 18, stated her independence, "It's the first time I've been away from my parents and it's hard. There's been so many good performance [that] you're like 'Oh, no, am I ready for this?' " And she was, judging by her sassy, soulful and pretty sexy rendition of Gavin DeGraw's "Sweeter." "Very spicy," L.A. Reid shared to his fellow judges.

The Boy-Band Dilemma
Considering that One Direction got their start on the U.K. version of the show, a number of new boy bands are trying their best to use the show as a launching pad, including L3vel, Jetset and Emblem3. L.A. recalled that Enblem3 "rocked it" during their audition, but their harmony-filled rendition of the Goo Goo Dolls' "Iris" later had him wondering, "Will you love them 20 songs from now?"

The Just Plain Bad
There were a number of contestants who blew through the boot camp and couldn't hit any notes or remember any lyrics, leaving the judges perplexed. Some of the sourest performances came from rapper Johnny Maxwell, 16, who couldn't recall one single line to Diddy's "I'll Be Missing You." (Though he did manage somehow to get through.) Then there was wannabe Internet star Trevor Moran, who famously stirred up some drama during his audition when he fell ill but couldn't stir up any positive reactions when he decided to perform Nicki Minaj's "Starships."

Diva Battle
Rihanna lookalike Paige Thomas and the Ke$ha-inspired Cece Frey had both prepared the Houston classic, "I Will Always Love You." The claws were out and after each lady belted out their version of the song, Simon had this message, "One of you actually nailed it." (Spoiler alert: Both ladies seemed to nail it, as neither got cut.)

Last Men (and Women) Standing
At the top of the show, Britney Spears said that there's "no second chances, you either stand out or you go home." By the end of the night, that was true for a number of the hopefuls. After a montage of the judges, well, judging among themselves, the contestants later learned their fates in groups. Two of the three groups made it through to the next day. Britney seemed particularly teary as the "no" group was told to pack their bags.

Who was your favorite performer during Wednesday night's "X Factor"? Leave your comment below!