10 Saddest Doctor Who Moments

One of the greatest pairings in the Whoniverse is without a doubt the Third Doctor and Jo. Their chemistry together was on point, and was built upon some rather shaky grounds. After all, Jo presented herself as a bumbling assistant in Terror of the Autons, something the Third Doctor wasn't keen to put up with at first.

The growth of their relationship felt so natural, with the Third Doctor helping Jo to expand through his teachings. Meanwhile, Jo also proved time and time again how resourceful she was on their adventures together.

Sadly, the Third Doctor was forced to face the fact that Jo was finally ready to move on, using everything she had learnt to fight her own battles against tyranny across the globe. Despite his happiness for Jo's engagement to Clifford Jones, he was deeply upset to see her go, knowing they were about to go their separate ways. It was such a close bond, so naturally it hurt them both to say goodbye.

It's made all the more tragic through Big Finish's The Legacy of Time, where a future Jo gives the Third Doctor some hints towards his personal future. This retroactively altered The Green Death, meaning he was already aware that their friendship was coming to an end.