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.

Lauren and Whitney go to Paris, but the trip is marred for Lauren when she finds out Brody is seeing someone new. Meanwhile, Spencer follows Heidi to Colorado to try to win her back.

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.

Loyalty lines are questioned when Stephanie Pratt makes nice with Lauren at FIDM. Plus, Whitney travels to NYC to jump-start her career with People's Republic.

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?

After the much talked about birthday party Lauren had, the talk of the characters on The Hills is Lauren's friendship with Stephanie. Audrina is approached by someone unexpected, much to someone else's discomfort.

Lauren is surprised by a job offer she receives. Meanwhile Heidi enjoys a night out with her friends, until she spots Spencer and things end up in a fight.

Lauren and Lo are looking into the real estate market as they plan to buy a house. Meanwhile, Audrina reconsiders her situation as a single woman.

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.

While Lo and Lauren enjoy living at the house, Audrina feels more and more left out. Meanwhile Stephanie thinks it's time to get rid of Spencer and Heidi prepares her next step in her career.

Lauren tries to uphold her friendship to Audrina, but is it already too late? Meanwhile Spencer tries to win Heidi back and risks her career to do so.

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.

Holly reaches out to Lauren, forcing Lauren and Heidi to reconsider their friendship. Meanwhile, Audrina and Justin's relationship is tested.

When Lauren is away for a couple of days, Stephanie and Doug start dating secretly. How long will that stay a secret though?

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 suprises Lauren when she moves out, and Heidi disappoints Brent Bolthouse when she invites Spencer to a work event and gets caught having a little too much fun.

Heidi decides to go back to Brent and Sam and ask for her job back. Plus, Holly Montag's crashing at Lauren and Lo's since getting kicked out of her sister's place.

A nasty rumor threatens to end Lauren and Audrina's friendship and Heidi realizes Spencer's been withholding information from her.

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.

In NYC, Whitney has an interview with Diane von Furstenberg and sees Jay. Plus, Lauren says goodbye to her Laguna home and Stephanie makes a difficult decision about Cameron.

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.

The season four finale finds Lauren and Heidi running into each other and are reminded why the once were best friends. Meanwhile, as Heidi's mom pays a visit, the she and Spencer know they must face reality; and Audrina is surprised by Justin with a trip to Palm Springs.

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.

After Heidi catches Spencer at a nightclub with Stacie the bartender, she demands they go to couple's therapy. Plus, Lauren puts her reputation on the line when she gets Stephanie an interview at People's Revolution.

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.

Lauren is put into an awkward situation after Stephanie messes up at work. Meanwhile, Justin calls out Audrina for hooking up with Brody.

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.

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.

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....

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

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.