Nick Jonas and Demi Lovato Nick Jonas and Demi Lovato

The remaining field of 60 contestants (down from the original 120) was  further whittled down to the top 24 during the final round of boot camp cuts on Wednesday's two-hour episode of The X Factor. The remaining contenders were assigned into four categories (six in each), and found out which judge would be mentoring them. Simon Cowell will handle the groups; Britney Spears will take on the teens; L.A. Reid is in charge of the over 25s; and Demi Lovato will help the young adults along. As an added twist — only three groups were chosen initially, but the judges assembled another three from some of their favorite performers who weren't selected individually.

All of the judges were happy with their assignments (which were chosen by the show's producers), with the exception of Reid, who initially slammed down the phone receiver upon getting the news and later told his mentees he was "disappointed" to be mentoring the oldest group. "I can't really say that there's anybody that stands out for me in the category, so I'm not happy," Reid said matter-of-factly. But, he vowed, "I'm still planning on winning." How heartwarming and supportive!

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Once the four sections were determined, the competition moved to the judges' homes — where the contestants found out which judge they would be working with and were also introduced to each judge's special guest mentor — Marc Anthony for Cowell; Nick Jonas for Lovato; for Spears; and Justin Bieber and his manager Scooter Braun for Reid.

Wednesday's episode highlighted Cowell and Lovato's groups, and Thursday's will focus on Reid and Spears' singers.

At the end of the judges' homes round, each judge will eliminate two contestants from his or her group, and bring the remaining four to the live competition phase, which begins on Thursday, Nov. 1.

Here's a rundown of the Top 24. Did your favorite contestant make the cut?

Teens: Beatrice Miller, James Tanner, Carly Rose Sonenclar, Diamond White, Reed Deming, Arin Ray

Young Adults: Cece Frey, Willie Jones, Jennel Garcia, Nick Youngerman, Paige Thomas, Jillian Jensen (Notable: Gene Simmons' daughter, Sophie Tweed-Simmons, wasn't chosen to advance)

Over 25s: Jason Brock, Daryl Back, David Correy, Tara Simon, Tate Stevens, Vino Alan

Groups: Pre-formed: Sister C, Dope Crisis, Emblem3; Assembled by judges: Playback, Lylas, Lyric 145

The X Factor resumes Thursday at 8/7c with more footage from the judges' homes round.