Doctor Who: 10 Best NuWho Villains That Only Appeared Once

9. The Midnight Entity

This is the one villain that even The Doctor knows almost nothing about.

Because of its claustrophobic setting, and cabin-feverish tone, which some might say reeks of low budget, Midnight is an episode that is almost completely reliant on dialogue, both to keep us engrossed and to keep the plot moving. But rather then hinder it, this provides a refreshing take on the usual Doctor Who storyline. You know the dance €“ Doctor journeys somewhere in space and time, Doctor encounters villain, Doctor saves the day. The amount of dialogue gives the actors a chance to shine, especially Lesley Sharp as Sky Silvestry under the influence of the Midnight Entity. She plays the entity with a real creep factor, especially after she has The Doctor under her control. Who would have thought that something as simple as copying someone's words could be so unnerving?

Throughout the episode the tension gradually builds, as we see the various stages of Sky's possession, which ranges in order from strange, to creepy, to downright terrifying, to kill it with fire. It all builds to a crescendo of a finale, where everyone is shouting, and we see The Doctor as we've never seen him before, truly afraid.

But the real testament to the Midnight Monsters impact, is that it turned what could have been a really dull episode, into one of the classic episodes of the David Tennant era.