Lauren hears that Heidi's been spreading rumors about her. When Lauren and Heidi run into each other, they have their biggest fight yet.
Lauren and Heidi grow even farther apart when Spencer asks Heidi to marry him. Audrina gets serious with a boyfriend from her past.
Lauren helps Audrina decide if Justin is boyfriend material. Heidi learns that being engaged isn't all fun and games.
Heidi takes her fiance to meet her family in Colorado. Audrina is crushed when Justin ditches her at Brody's barbecue. Lauren admits she misses Heidi.
Heidi's social circle shrinks as Spencer "breaks up" with Brody. Audrina her relationship with Justin to be official, but he refuses to commit.
Lauren gets a blast from the past when her ex-boyfriend Jason calls. Heidi competes with her co-worker Elodie for a promotion at work.
Lauren's feelings for Jason are rekindled but Heidi and Spencer cause tempers to flare. Heidi's promotion at Bolthouse costs her Elodie's friendship.
Lauren learns that Jason has a girlfriend. Heidi finds out Spencer didn't his parents about their wedding plans. Whitney parties before a photo shoot.
Justin causes a rift in Audrina's friendship with Lauren. The attraction between Lauren and Brody grows. Heidi and Spencer's anniversary is cut short.
Jen Bunney tells Lauren that Brody started the rumors about her. Lauren apologizes to Audrina for interfering in her relationship with Justin.
Lauren embarks on a new romance with a male model but realizes she still has feelings for Brody. Spencer fears that he's losing Heidi to her new job.
Lauren and Whitney are sent to New York City, where Whitney attempts her first presentation to Teen Vogue. Brody isn't ready to forgive Spencer.
Lauren and Whitney struggle to put on a fashion show. When a new guy shows interest in Audrina, Justin takes their relationship more seriously.
Heidi and Lauren have another fight in public. Audrina's relationship with Justin is stuck in a rut, but her career is taking off.
Whitney goes on her first date with their personal trainer. Spencer resists Heidi's plans for a fairy-tale wedding, resulting in a fight.
Audrina catches Justin kissing another girl. Heidi is shocked when Spencer's sister, Stephanie, picks a fight with Lauren and Brody at a nightclub.
Lauren thinks Brody is a playboy. Spencer's sister tells him that Heidi is having doubts about their wedding. Audrina goes out on a first date.
An offer to work in Paris complicates Lauren and Brody's relationship. Heidi questions her future with Spencer and decides to leave Los Angeles.
Lauren's Paris trip is almost ruined when she finds out that Brody has found someone new. Spencer chases Heidi to Colorado to try to win her back.
Whitney must choose between her job or a risky new career. Lauren and Brody clash over his new girlfriend. Heidi adjusts to life without Spencer.
Lauren makes an unlikely friend when Spencer's sister, Stephanie, joins her fashion class. Whitney thinks her new job is a dream come true.
When Lauren invites Stephanie to her birthday party, Heidi and Spencer question Stephanie's loyalty. Spencer launches a plan to win back Heidi.
Heidi tries to win back Audrina's friendship, but Lauren grows suspicious of Heidi's motives. Whitney discovers that she misses working with Lauren.
Heidi loves her single life — until seeing Spencer with other girls makes her jealous. Whitney enlists Lauren's help during LA Fashion Week.
Heidi makes a last attempt to regain Lauren's friendship. Lauren questions whether she and Audrina should continue living together.
An old romance is rekindled when Stephen Colletti reenters Lauren's life. Heidi tries to prevent Stephanie from attending Lauren's housewarming party.
Heidi accepts a job opportunity that will take her to Las Vegas. When Stephanie kicks Spencer out, he returns to Heidi but it may be too late.
In the season finale, Audrina feels shut out by Lauren's friendship with Lo, and wants to move out. Spencer fears he's going to lose Heidi forever.
Tensions reach a breaking point between Audrina and Lo. Later, Spencer and Heidi's relationship is threatened by a visit from her sister.
When Lauren runs into Spencer at Stephanie's party, the birthday girl finds herself at odds with her brother and her friend.
Lauren realizes the chemistry she had with Doug in high school may no longer be there, and Whitney is nervous about going to New York City for work.
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.
Lauren and Audrina try to save their friendship. Meanwhile, Spencer has had enough of Heidi's sister and takes matters into his own hands.
Holly reaches out to Lauren, forcing Lauren and Heidi to reconsider their friendship. Meanwhile, Audrina and Justin's relationship is tested.
Lauren leaves for family vacation, and things in Los Angeles go awry. Stephanie dates Doug behind Lauren's back, and Audrina and Heidi get friendly.
The truth comes out about Stephanie's relationship with Lauren's ex-boyfriend Doug. Meanwhile, Heidi's mother pays a surprise visit to Los Angeles.
Lauren gets a letter of apology from Heidi. Elsewhere, Audrina starts dating a new guy to make Justin jealous, but her plan backfires.
Audrina reconnects with an old flame Cory and finds herself juggling two guys. Spencer forces Heidi to kick her sister Holly out of the apartment.
Lauren and Audrina travel to Cabo for Brody's birthday, but when Justin gets jealous, the party turns into a fight.
Lauren tries to make peace between Brody and Stephanie. Meanwhile, Audrina wants to make things work with Corey, but Justin won't give up on her.
Audrina gets her own place hoping that Justin will move in with her, but everyone fears she's moving for the wrong reason.
Whitney travels to New York City expecting to reconnect with Alex, but a new boy steals her away. Meanwhile, Heidi is miserable after being fired.
Heidi's sister crashes at Lauren's place. Meanwhile, Heidi's frustration with Spencer grows after she has to beg for her job back.
A rumor about Lauren and Justin threatens to ruin Lauren and Audrina's friendship for good. Heidi catches Spencer in a lie about Holly.
Audrina tries to save her friendship with Lauren after accusing her of hooking up with Justin. Spencer and Stephanie visit their grandmother.
Whitney is offered a chance at her dream job in New York City and hopes to see Jay while she's in town.
Spencer and Heidi run away to Mexico to elope. Meanwhile, Whitney takes a job in New York City and says goodbye to Lauren and life in Los Angeles.
After Lauren and Heidi have a run-in, they put their feud aside and remember why they used to be friends. Later, Justin takes Audrina to Palm Springs.