丰富的知识、充满魅惑的舞会、以及帅气的鼓手史蒂芬（凯姆•吉甘戴Cam Gigandet 饰）让刚迈进大学校门的女孩子莎拉（敏卡•凯莉 Minka Kelly 饰）兴奋不已，而友善的室友蕾贝卡（莉顿•梅斯特 Leighton Meester 饰）则让她的大学生活显得更加完美。然而，生活并不像表面那样平静，蕾贝卡乖戾的性格渐渐显露，她不仅恐吓与莎拉亲近的好友崔西（艾莉•米夏卡Alyson Michalka 饰）远离莎拉，而且因为莎拉要搬走，残忍的杀死了莎拉的宠物猫。蕾贝卡怪异的占有欲让莎拉感到恐惧，她终于忍受不了自己的病态室友，决定远离这一切，然而事情并没有那么简单……
本片集结了当前几部热播美剧中的俊男美女，加之取材于报纸上真实报道，在该片未上映之前便为本片攒足了噱头。

It was reported that in season 2, Dixon and Silver's relationship will suffer due to two new characters, Sasha, an African-American woman who pursues Dixon, and Teddy, a tennis champ who pursues Silver and later Adrianna. Annie will also go through hard times and feel isolated from the group, Dixon will abandon her because he gets "sick of her drama" when nude photos of her surface. Silver will reconnect with old friends Adrianna and Naomi.
Season two has also been reported to be darker than season one, taking the viewer far further than the famous but fabled Peach Pit. Like in its NYC counterpart, Gossip Girl, 90210 season 2 will be exploring L.A.'s social scene, using real clubs and restaurants for scenes of drama. The fashion of the show will also change, being more incline to Gossip Girl 's, where the outfits are chic and trendy. Season 2 kicks off on September 8, 2009 at 8:00pm on The CW.