10 Best Doctor Who Characters Only In One Episode

Played to perfection by the legendary Michael Gambon, Kazran Sardick is one of the most fleshed-out side characters in Doctor Who history.

We first meet him as an adult, where he seems to have just one note: grumpy. But as the episode proceeds and slowly peels away that cold exterior to reveal the optimistic child and troubled teenager underneath, we learn exactly why the old Mr. Sardick is as miserable as he grew up to be: an abusive father, the need to continue in the family business, and a lost love all combined to turn him into a Scrooge-like monster.

The revelation of Kazran's complicated backstory is so expertly done that you might actually start to feel guilty about finding him a miserly old codger in the first place, and on top of his excellent storyline and satisfying heroic turn, Kazran also had the booming voice of Gambon to make him a dominant screen presence.