3. Leela
Anyone trying to follow Sarah Jane Smith is in for a hard time. But the producers of Doctor Who at the time, well aware of this problem, replaced our beautiful, sweet and decidedly well-dressed reporter with a wild, leather bikini-clad savage from the future. And it worked. Louise Jameson's Leela was was as wild as they get when she first meets the fourth Doctor, but quickly becomes loyal to her new-found friend, if often quite confused by what her puts her through. And how is she repaid for this loyalty? By being shown that she is only complete when she has a man. Yay for women's rights and stuff. In reality, Jameson had accepted a role elsewhere, and decided her time as Tom Bakers favorite person to dislike was done. So in The Invasion of Time, Leela meets a dreamy guy. They say, oh, maybe 10 words to each other. And, like you do, decide to get married. The Doctor, understandably baffled by this turn of events, basically says Good riddance, and you can keep K-9 too. He didn't care much, you see, as he promptly wheels out a box with a new K-9. Cheeky.