Audrina

To kick off season 3 of The Hills, Audrina moves in with Lauren and into Heidi's old bedroom. The girls are giddy with excitement over becoming new BFFs. But before Audrina and Lauren can partner up to hit the Hollywood dating scene, Audrina falls for a guy she thinks could be "the one." Even though she's working really hard to make the transition from serial dater to serious girlfriend, it remains to be seen whether all those years of kissing frogs is going to pay off. Has Audrina finally found her prince or will she push aside love for the glamorous L.A. nightlife? But finding Prince Charming isn't the only thing on Audrina's mind. Audrina is still working as a receptionist at Epic Records, but with Lauren and Whitney taking on more responsibility than ever at Teen Vogue, Audrina realizes that she is also looking for more challenges at work. Plus, she'll try to get Lauren to help her plan a wedding that no one saw coming. With so much going on, Audrina is more than happy to have Lauren by her side. But as the two settle in together, they'll discover there are things they could only learn about each other as roommates.

Heidi

On the surface, Heidi has everything she could have ever wanted in life -- a prestigious job promoting the hottest Hollywood parties; a boyfriend she utterly adores in Spencer; a great apartment in the fabulous Hollywood Hills; and, hopefully, a gorgeous engagement ring waiting just around the corner. With all of that, though, she's still missing one very important thing: her best friend Lauren. That's why season 3 of The Hills is going to be the hardest year yet for Heidi. After Heidi and Lauren came to blows over Spencer's two-timing ways, Heidi moved in with Spencer and hasn't spoken to Lauren at all. And the rift between them is only getting bigger since Audrina moved in with Lauren and seemingly replaced Heidi. Now Heidi is heading toward the most important decision of her life, as Spencer gets ready to pop the question. But the moment won't be as magical if Heidi doesn't have her best friend Lauren to share it with. As wedding bells approach, is Heidi on her way out of Lauren's life forever or will she eventually convince Lauren to accept Spencer for who he is? No matter what happens, things are definitely going to get interesting.

Lauren

During season 3 of The Hills, Lauren has more things to deal with than ever. She faces new pressures at work as she and co-worker Whitney prepare for their biggest challenge yet at Teen Vogue. She also has a new roommate and a new wing woman in Audrina, and the two of them are hitting the Hollywood dating scene in a big way. Lauren is determined that this is the year she'll find Mr. Right. But one of Lauren's ex-boyfriends always seems to be lurking in the shadows. This time around it's Jason, who is trying to put his life back together and decides to reach out to Lauren for help. Can Lauren and Jason really be "just friends" after everything they've been through? Only time will tell. On top of all that, Lauren hasn't spoken to BFF Heidi since Heidi moved in with her two-timing boyfriend, Spencer. But with Heidi going through as many ups and downs as Lauren, it won't be long before she misses her best friend. What will Lauren do if and when Heidi decides she wants to patch things up? Lauren has certainly learned from her past mistakes, but anything can happen on season 3 of The Hills!

Whitney

Out of all The Hills girls, Whitney's life will change the most dramatically during season 3. She's finally graduating from college and is being promoted from intern to employee at Teen Vogue, where she works with Lauren. Whitney's got a lot on her plate -- she's facing the pressure of a new job, new bosses and being a new boss herself! Will she crack under the pressure or step up to the plate? Whitney and Lauren have been friends for a long time, but that friendship will have to take a backseat to Whitney's career when Whitney becomes Lauren's direct supervisor. It's certainly going to be tough being Lauren's new boss! Will their friendship become strained when Whitney has to put her foot down at work or will they grow closer than ever? The biggest change in Whitney's life, though, is her painful breakup with her longtime boyfriend. But hopefully she'll find out just how much fun L.A. can be for a newly single girl. Luckily, she couldn't have two better friends than Lauren and Audrina to get her back on her feet and guide her through the Hollywood dating scene. Yes, some big changes are definitely on the horizon for Whitney.

Stephanie

Ever since she made friends with Lauren, Stephanie has been on thin ice with her brother Spencer. And inviting Lauren to her birthday party might be the last straw. Lauren's friends don't trust Stephanie, and Brody isn't afraid to tell her so to her face. Stephanie relies on Lauren, who sticks up for her every chance she gets. But when Stephanie goes after one of Lauren's boys, she realizes she may have lost her last ally.

Lo

Lo is about to graduate from college and enter the working world, but first she has to take care of business at home. She feels that Audrina has refused to put any effort into their friendship and she's not afraid to say so. Lo wants everybody in the house to get along, but she's also starting to think that she and Audrina will never find a way to be friends. Maybe they can co-exist in peace -- or maybe it's time for one of them to move on.

Spencer

Spencer made the big play in Vegas and won Heidi back, but he also got her in trouble at work and has a lot of making up to do. Just when he convinces Heidi to move back in and get their lives back on track, Heidi's sister Holly shows up in LA and moves into their apartment. Spencer has to find a way to get rid of Holly to save his sanity and his relationship with Heidi. But Holly's not the only sister causing trouble. Spencer's own sister, Stephanie, has become good friends with Lauren and Spencer feels completely betrayed. When he sees that both he and Lauren have been invited to Stephanie's birthday party, he plans a surprise for Stephanie, then plans to cut her out of his life for good.