In episode 4.02 of 90210 (airing tonight - September 20), Naomi decides to rush the most popular sorority on the CU campus.  Want to know how that turns out?  We've got spoilers for upcoming episodes for you.

Episode 4.03 "Greek Tragedy" (September 27): I can tell you that Naomi's attempts to join the sorority end with her making a brand new enemy out of sorority president Holly (guest star Megalyn Echikunwoke).  When Naomi decides to take her revenge, she finds herself some "unusual allies".  Annie makes it through the sorority games, but finds it difficult to come up with the money for the dues now that Marla's inheritance is tied up since the family is contesting the will.  In tonight's episode, Liam will be getting a surprise visit from Alaska: a woman named Jane (guest star Kristina Apgar).  In episode 4.03, the pair will get closer.  Adrianna will also get closer to Liam and will tell him a secret that makes Liam look at her differently.  Ivy continues to struggle with Raj's illness and lashes out at her friends when she believes they're not being particularly compassionate.  Navid gets an unpleasant surprise when his uncle comes to town and tries to interfere in the way Navid is running Shirazi Studios.

Episode 4.04 "Let the Games Begin" (October 4): Navid messes up Dixon's interaction with a music producer so he gives Dixon some time in the studio as an apology.  But while the gesture is nice, Dixon feels very pressured to create a hit song.  Naomi and Holly's rivalry continues and Nomi wants to take Holly down during the Greek Games, but she's forced to call on Austin for help, which seriously angers her.  Silver, now working at Shirazi Studios with Navid, directs a commercial for Liam's bar that turns out to be a disaster.

Also, did you hear that Billy Ray Cyrus will be making a guest appearance on 90210?  EW reports that he's been cast to play Austin's father, Judd Ridge.  Cyrus' episode will air in November.

Don't miss an all new episode of 90210 tonight at 8:00 p.m. on The CW.  View a trailer, sneak peek and photos for tonight's episode.