Doctor Who S4.5--Planet of the Dead

I did like this one, though.  The Doctor is on a bus for whatever reason, and he meets a girl who just stole something from a museum.  When all of a sudden, the bus goes through a wormhole and disappears into another world.  There's only sand, everywhere.  One of the women says she can hear their voices, their voices crying out as they die.  The thief, Christina, takes charge.  She and the Doctor get kidnapped by these fly-looking creatures.  They discover a swarm of something that is coming, towards them and opening a wormhole.  They also discover that the sand around them is a planet that was destroyed by the swarm and that the swarm is going to do the same to Earth.
They retrieve anti-gravity claws, attach them to the bus, and they fly through the wormhole.  The hole is closed by possibly the Doctor's biggest fan, ever.  Christina asks to go with the Doctor, but he refuses, because he can't handle losing someone else.  The psychic lady who hears things tells the Doctor that he's going to die, soon, and that his death would be heralded by four knocks...