Midnight is the tenth episode of the fourth series of the revival of Doctor Who, starring David Tennant as The Tenth Doctor and Catherine Tate as Donna Noble. Due to the shooting schedule of the show, this is a companion lite episode, with Catherine Tate only appearing at the beginning and end of the episode.
The story takes place on the planet Midnight, where the Doctor takes a "big space truck" across the surface of the planet to watch a waterfall made of sapphires. But the vehicle breaks down. The Doctor, along with about ten crew and passengers, is stuck on the hostile surface of the planet. And something seems to have gotten into the ship with them.
Whatever it is, it is intangible. But it seems to be possessing one of the passengers, making her repeat everything anyone says. And then the possession passes to the Doctor, as the increasingly frantic passengers try to figure out what is going on. The situation is saved at the last moment, although not anywhere near in the heroic fashion we have come to expect of Doctor Who.
Apparently, opinion on this episode is divided. It has none of the usual charm and wonder of Doctor Who. Almost the entire episode is set inside the interior of the vehicle, with very little in the way of scenery or special effects. This is what is called a bottle episode, with the entire set being something that could be whipped up for a community college drama production. But in my opinion, it works. The passengers and their rising hysteria from being trapped in a small, bleak space works in a way here that it could not work in an epic battle scene. And this is the only Doctor Who story I can think of where The Doctor's usual charm and wits fails to save him.
This episode also highlights one of the things that new viewers can find a problem with Doctor Who: the uneven emotional pacing and impact of the show. In this episode, only four people die, which compared to some Doctor Who episodes is a relatively small number. Voyage of the Damned had thousands of people killed, including a companion, and yet it was treated as light fare. This episode has a much smaller number of deaths, and yet it could be considered one of the most bleak episodes, the only episode where we see the Doctor truly defeated. For some people, this doesn't make sense, and for others, this is what the show is about.