I was all ready to write a happy post about the return of Doctor Who this Saturday on BBC America...but then things got sad.

Elizabeth Sladen, who portrayed one of the most loved and best companions of all time, Sarah Jane Smith, died yesterday due to cancer.

I am a relatively new fan to the Who-verse, meaning I started watching with the Ninth Doctor, but Sarah Jane's episode with David Tennant ("School Reunion") and K-9 was one of my favorites. The actress impressed me with her talent, and the character impressed me with her smarts, spunk, and obvious love for the Doctor. I also really enjoyed her spin-off series The Sarah Jane Adventures. And don't forget that Sarah Jane was back for the two-parter "The Stolen Earth" and "Journey's End" (along with a lot of the newer companions) to help bid David Tennant's time on the show a fond farewell.

The point of all this blabbering is that Sarah Jane was truly a cornerstone of the Doctor Who world, both to fans of the classic series and the newer incarnation alike. All yesterday people involved with the show tweeted and commented about the impact she had on the show, and I know she will be truly missed. Maureen Ryan over at TV Squad has a nice write-up about Elizabeth Sladen, and I recommend you check it out.

As we move forward with the newest season of Doctor Who on Saturday, take a moment to remember all the people who have been involved in this show over the past 50 years. It's more than just a television program--it's truly a part of our cultural history.