10 Doctor Who Secrets Everyone Knows But You
6. The Original Sarah Jane Smith
This particular story is one that hardcore Whovians will definitely be familiar with, but more casual fans might not know that we came startlingly close to never having Elisabeth Sladen as legendary companion Sarah Jane Smith.
Sladen debuted in the role in 1973, but Sarah Jane almost looked very different to how we know her today.
The part was originally given to actress April Walker, best known for her appearances in classic British comedies such as The Two Ronnies and Fawlty Towers. The producers of Doctor Who thought that Third Doctor Jon Pertwee wouldn't mind Walker's casting, as the two had previously worked together.
How wrong they were.
During rehearsals, it became clear that the chemistry just wasn't there, with Pertwee reportedly complaining about Walker being taller than he was. And so, that was the end of that, and Sladen was brought in as Walker's replacement.
It's hard to imagine anyone else playing the part of Sarah Jane, but one has to feel sorry for Walker, who just missed out on the role of a lifetime. Rough.