VIDEO: First Look at 90210's 100th Episode

In the 100th episode of "90210", the gang goes back to high school, confronting memories (and cast members) from seasons past, with special guest appearances by Denise Richards and Carmen Electra. Check out a preview of the episode below!

The 100th episode of 90210 is set to air Monday, December 3 (8:00-9:00PM, ET/PT) on The CW.

The fifth season of 90210 finds the gang struggling with the biggest issues of their lives. Having put their relatively carefree days at West Beverly behind them and launched themselves into adulthood, they search for answers to their trials and tribulations with only their friendships to lean on.