Heidi Montag drops by The Abbey. Marissa's mom travels to L.A. to try to convince her baby to come home. Lawrence and Brandi find out if they're 'fit' to be parents. Cory and Murray's relationship reaches a breaking point.

After Kyle learns Marissa has a boyfriend back home, he sets his sights on another. Cory decides to try to work through his issues with Murray, but it doesn't last long when drama unfolds at Lawrence's charity event. Elizabeth has a meltdown and causes a scene when she feels she's been "disrespected" by Kyle.

The Abbey crew heads to Palm Springs for a photo shoot where Billy and Ashlee heat things up. Chelsea can't manage her anger towards Ashlee and Murray after Kyle instigates a rumor.

Kyle thinks his relationship with Marissa is on the right path, but Marissa pumps the brakes. Ashlee meets Billy's brothers, while jealousy threatens to derail Kim and Elizabeth. Brandi and Lawrence hit a roadblock on their journey to become parents, will Brandi change her mind? Kyle has a major party foul when he reveals a juicy threesome rumor involving Kim, Lawrence and Cory.

The crew heads to Vegas where trouble starts to brew for Elizabeth and Kim. Kyle grows more confused when Marissa plays hot and cold with him. Cory and Murray decide to make a pact to keep their relationship in one piece while David reaches the end of his rope with Chelsea.