The DVD for "Planet of the Dead" is an hour-long special originally aired on Easter, but if you're familiar with the Doctor Who specials then you know that they have very little to do with the holiday they land on. Also included on the disk is a 60-minute making-of featurette, with standard behind-the-scenes stuff.
The scene is set with a robbery of some high security museum. We don't know what's stolen but we do know it was very valuable with our robber running from the cops and onto a bus. This is when the Doctor shows up. He sits right next to the robber who we find out is Christina (Michelle Ryan).
The Doctor is tracking a hole in space and time, which the bus quickly drives through and into a barren desert planet. The Doctor — left without his TARDIS — has to help the people on the bus get home before a mysterious sand storm that one of the passengers calls "Death," hits them.
The Doctor is helped to lead the passengers by Christina, and while they work together, they learn that they are a great pair. And they really are: Christina is a welcome change from the Doctor's usual companions. She has a rebellious attitude, and doesn't mind getting her hands dirty, plus she shares the love of adventure that all of the Doctor's companions have.
The episode is chock full of great Doctor Who moments like when the Doctor is able to inspire the group to believe in him, and you do to, or when the Doctor is talking to a UNIT scientist and makes fun of him for naming a unit of measurement after himself. This episode is full of what makes Doctor Who great, minus the Tardis.
If you want a taste of Doctor Who then this would not be a bad way to go because it is self-contained and represents the show well.