Lauren faces the aftermath of her decision to opt out of her summer internship, Whitney returns from her internship, and Audrina and Heidi find themselves in a major feud over a new guy.

Heidi finds out the results of her pregnancy test while Lauren and Whitney are asked to cover a major fashion show. Meanwhile, Audrina turns Spencer down when he asks her out on a date.

Heidi throws a party for her birthday where Audrina shows up to try and make amends. However, Heidi refuses to listen.

Heidi and Audrina go out to have dinner and they finally talk about their issues and Spencer.

Lauren is not at all thrilled in Heidi's decision to get back together with Spencer. The situation between best friends becomes even more heated and leaves their relationship hanging.

As if Lauren's falling off with Heidi wasn't enough, another one of her eldest friends, Jen, has eyes for Brody. Jen feels guilty for hooking up with Brody but Heidi encourages her to go for what she wants. Clearly, there is a lot more to mend in their relationships and Lauren assures Heidi that they'll never be the same as long as Spencer's still in her life.

Heidi decides to throw Lauren a surprise 21st birthday party and tells her about Spencer asking her to move in with him. Jen tries to apologize to Lauren but instead makes excuses, thus, Lauren doesn't accept her apology.

Whitney flies to New York City to apply for a new job at Teen Vogue. Meanwhile, in Los Angeles, Heidi gets a call from Spencer who has a huge surprise for her.

The third season premieres with Lauren and Heidi still unable to get past their differences and having become mortal enemies. Meanwhile, Whitney has graduated from college and is now juggling a real job and Audrina has become Lauren's new roommate and best friend.

Lauren returns to Laguna Beach for some advice. Meanwhile, Audrina and her new beau get serious with their relationship and Spencer proposes to Heidi.

Audrina invites Lauren out to dinner to get to know Justin better. Lauren is not impressed by him. Audrina talks to Justin and decides to give their relationship time. Spencer suprises Heidi by buying two arcade games for the apartment. Later, she suprises him by painting over the mural in the living room.

Spencer and Heidi go away for the weekend to meet Heidi's parents, causing Spencer to flake on his and Brody's barbeque. Lauren, Audrina, Lo, and Justin Bobby attend. Justin Bobby flirts with other girls and leaves Audrina at the party, and Lauren finally realizes that she and Heidi will never be friends again.

Just when everyone believes that Justin Bobby is finally history, Audrina decides to rekindle the relationship, much to Lauren and Lo's surprise.

Brody celebrates his birthday in Las Vegas and of course Lauren and her friends are invited too. Meanwhile Heidi has to face more problems at work than she likes.

When Jen wants to be friends again with Lauren, however the dark past starts to haunt everyone. And not everyone likes the past revealed.

Lauren goes out with one of the male models from a photo shoot, leaving Brody to question everything that has developed in the past weeks.

Whitney and Lauren are sent to New York to present their ideas about the big fashion show. Meanwhile Franky tries to fix Brody's and Spencer's friendship.

Lauren and Audrina find out that Spencer has a sister. She also pays Spencer and Heidi a visit. When Lauren and Audrina hang out with Brody, they not only run into Spencer's sister, but also run into Justin - with another girl.

Stephanie tells Spencer that Heidi might bail out of the wedding, so Spencer and Heidi fight once again. Lauren and Audrina both have a date.

Broken hearts as far as the eyes reaches: Heidi and Spencer can't agree on their wedding plans while Brody and Lauren both refuse to make the first step.

After their week in Paris, Lauren and Whitney are back home and have to adjust to the changes and the changes they plan to do.

It's Lauren's birthday and for some guests an appearance at her party could mean a lot of trouble. Also from whom will Lauren receive a birthday kiss?

The girls go out to find a new home. When they find one, the guest list for the housewarming party is subject to more than just one fight.

The tension between Lo, Lauren and Audrina continues and soon things reach boiling point.

Stephanie's birthday party is around the corner and so everyone tries to make an appearance. Also things start to change for Whitney.

Whitney's love life starts to heat up while Lauren's starts to cool down. Meanwhile Heidi and Spencer fight.

A blowout trip to Las Vegas turns sour when Audrina snubs Lauren, Brody brings up Stephanie's past and the boys end up in jail.

Brody is still in jail, so the girls try to come up with a way to get him out. Plus Audrina and Lauren finally sit down and talk to each other.

Doug and Stephanie have to explain themselves to Lauren. Meanwhile Heidi's mother pays a visit.

Spencer sets an ultimatum for Holly to move out. Meanwhile Audrina checks which boy is best for her. Will it be Justin?

Lauren and Audrina travel to Cabo for Brody's birthday, but Audrina's problems with Justin threaten to ruin the festivities. Back in LA, Spencer gives Stephanie's new boyfriend a hard time over dinner.

Audrina wants to make things work with Corey, but finds herself torn when Justin drops by Epic. Meanwhile, Stephanie starts having doubts about her new boyfriend when he fails to defend her in front of Brody.

Audrina tries to make amends with Lauren after the fall-out. Then it's off to Nana's house where Spencer and Stephanie compete for their grandmother's affection.

Spencer and Heidi ignore the concerns of their families and elope in Mexico. Meanwhile, Whitney says goodbye to Lauren and her life in Los Angeles as she leaves for her dream job in New York City.

Lauren lands in tears during her surprise birthday party when Heidi rocks the boat by showing up uninvited. Plus, Spencer takes a swing at Stephanie's ex-boyfriend, Cameron.

Heidi and Spencer evaluate their relationship after the bar scene and Lauren scolds Stephanie for pushing Heidi on her.

As Audrina tries to get over Justin, she sees Brody in a new light. Plus, Heidi drags Spencer to couples' therapy and Stephanie has a hard time handling work at People's Revolution.

Things heat up between Audrina and Brody in Hawaii and Heidi's ex-boyfriend, Colby comes for a visit.

The gang make their return to Los Angeles. Meanwhile, Brody and Audrina deal the repercussions from their hookup in Hawaii.

Spencer has an important question to ask Heidi's father when he comes for a visit. Meanwhile, Lauren make the decision to fire Stephanie from People's Revolution.

Spenser is asked by Heidi to make amends with Lauren in hopes that she'll attend their wedding. Elsewhere, a recently fired Stephanie has a run-in with Kelly Cutrone, her former boss.

Heidi and Spencer head down the aisle and two unexpected guests manage to attend the ceremony.

Kristin makes a big first impression in The Hills when she gets in a fight with two different women over one guy, works her way to queen bee status and lands a hot date with a motorcycle all in one episode.

Kristin kicks her pursuit of Justin into high gear after Audrina blows her off, while Heidi and Spencer's opposing views on kids causes trouble.

Justin doesn't show up at Brody's party and Audrina has a new target.

Justin tries to make up with Kristin. Heidi thinks something is wrong with Holly.

Heidi and Stephanie sit Holly down for an intervention when she continues drinking. Plus, Kristin gets upset with Justin's head games and Brody and Jayde get into a fight that leads them to reconsider their relationship.

Justin finds himself in hot water after Kristin and Audrina meet. Heidi wants to have a baby, but Spencer has another plan.

Audrina gets her heart broken when Justin ends things for good, it's a war of the exes over Brody, and Spencer considers drastic measures to stop Heidi's baby obsession.

While on a lunch date, Kristin and Brody recall the crazy times they used to have together. After Brody toasts to having a nice lunch without fighting, Kristin mentions that Jayde wants to talk with her. Brody tells Kristin she's out of her mind ...

Kristin is in Malibu packing up her beach house when she tells Stacie she doesn't want to pursue a relationship with Justin Bobby. Kristin says things were perfect when they were in Vegas, but she knows real life isn't like vacation.

Heidi heads home to show her family her post-surgery look, and Kristin's all-night partying begins to worry Audrina, Lo and Stephanie.

Stephanie gets blamed for spreading the rumors about Kristin's drug abuse problems, and Spencer lashes out when his sister approaches him at a party....

Kristin urges Audrina to commit to Ryan, then moves in to get closer to Brody and Spencer causes as scene when he gets angry with Holly at Enzo's party....

Heidi and Spencer's behavior cause their friends and family to make a difficult choice, while Kristin and Brody hook up but agree to stay single.

Brody puts his friendship with Kristin on the line when he starts seeing another girl. Lo sets Stephanie up on a double date....

Kristin has a hard time moving on from Brody. Audrina bumps in to Justin and starts to have doubts about her relationship with Ryan.

When Justin Bobby shows up onstage at a show Audrina, Steph and Lo are at, all the girls are surprised.

Audrina's relationship with Ryan is put to the test when he meets Justin for the first time. Brody sides with Kristin when Allie picks a fight with her.

It's Audrina's birthday and the gang, including Justin, board a boat at Marina Del Ray to celebrate. Elsewhere, Kristin has another run in with Allie at a club where a fight erupts. Also Audrina breaks up with Ryan and Kristin warns McKaela to stay away from her.

The gang heads to Costa Rica for a group surf trip, and Brody gets jealous when Kristin hooks up with a local bartender. Meanwhile, Audrina fights her attraction to Justin, and Stephanie finds herself at odds with the jungle environment

Brody and Kristin have a heart-to-heart, she wants to give their relationship another shot and Stephanie starts seeing someone new.

In the final episode of The Hills, there will be goodbyes, tears, promises, love and heartbreak. Kristin will have to decide if she's going to make a major change in her life, which may force Brody to make a decision about their relationship. Audrina chooses a new, independent life without Justin, but will that be the right choice? Lo weighs whether or not to take the next step with her boyfriend, and Stephanie, for the first time, believes that she's found true happiness.