The six young adults ride in a limo, speculating on who their mentor is going to be. The fact that they're in Los Angeles doesn't really narrow it down, though. They show up at a loft and wait, jumping up happily when Demi comes out. Of course their judge was going to be the only one who doesn't own a house. Her guest mentor is, who else, Nick Jonas. I remember when they were in a heavily-marketed cable TV movie together, because the store shelves were packed with unwanted Camp Rock merch instead of the Wall-E stuff my kid was after that summer. I'm over it, though. Mostly.

In Malibu, the teens get to ride in an SUV to Britney's hillside home overlooking the ocean, and wait excitedly by her pool until she comes out. Her guest mentor: will.i.am. The teens are pretty excited to see him, but I bet they'd rather have L.A.'s guest judge.

Speaking of whom, the Over 25s limo to another house in Beverly Hills, and are blown away by the place. L.A. comes out and pretends to be as happy to see them as they are to see him -- for about five seconds. He confesses that he was disappointed at first, but "I gotta now figure out how to get one of you guys to win." I'm sure they find his confidence infectious. So then he brings out Justin Bieber and his manager, Scooter Braun. Of course Justin Bieber has a manager named Scooter. Justin gives them some encouragement, which L.A. interprets to say that they're going to prove him wrong. "One of you is," he amends. Aim high, L.A.

We come back to Demi's "house" in L.A., which currently contains six Young Adults scattered around rehearsing, and Demi reminds us that she can only take four of them to the live shows. Each of them gives the interview camera an emotional speech about how much they want this. Demi sits down with Jennel and advises her not to nervously flip her hair so much before she goes up to the living room to sing "I Kissed a Girl" by Katy Perry for Demi and Nick. She performs it with a small guitar/piano combo, loud enough and well enough to make the others on the floor below look a little nervous. Jennel is a little thrown by the awkward silence from the mentors both before and after her performance, and after she leaves the room, Demi's only concern is how personally Jennel seems to have taken the mildest criticism. I agree that's going to make the completion tough for Jennel, especially when we mooks on the internet start weighing in.