Tension between Audrina and Lo reaches a breaking point; Lauren and Lo throw Audrina a birthday party; a visit from Heidi's sister threatens her relationship with Spencer.

Audrina feels shut out by Lauren's friendship with Lo; Spencer fears he will lose Heidi forever.

Tension builds between Lo and Audrina; Heidi accepts a job in Las Vegas; Stephanie kicks Spencer out.

Lauren finds romance when Stephen re-enters her life; Heidi tries to prevent Stephanie from attending Lauren's housewarming party.

Heidi makes a last attempt to regain Lauren's friendship; Audrina spends more time with Heidi and Justin.

Heidi enjoys being single until she sees Spencer with other women; Lauren helps Whitney during Los Angeles' fashion week.

Heidi tries to win back Audrina's friendship; Lauren is suspicious of Heidi's motives; Whitney adjusts to her new job.

When Lauren invites Stephanie to her birthday party, Heidi and Spencer question her loyalty; Spencer launches a plan.

Lauren befriends Spencer's sister in her fashion class; Whitney believes her job is a dream come true.

Whitney must choose between Teen Vogue and a new career; Lauren and Brody clash over his new girlfriend; Heidi adjusts to life without Spencer.