Synopsis: The Doctor, traveling completely alone, lands on a barren world whose surface is littered with the debris of several different space-faring cultures. No sooner has he exited the TARDIS as he's put in a paralysis ray by Cothax and Major Arn. The two are from the "Mighty Tragellan Empire", and, like the Doctor, they have been mysteriously pulled to the planet. Despite their accidental arrival, though, they mean to plant a flag on the planet and claim it for Trigella.
As they attempt to do so, the planet responds to the puncture of the flag pole. It sends up great, silicon-based beasts from its belly. As the paralysis beam abates, the Doctor begins to understand what's going on.
The planet is in pain, and has been drawing spacecraft to its surface, hoping to find some help. The Doctor lives up to his name and uses the Trigellans' weapons to cook up a Band-Aid® for the planet.
The "skin graft" seems to work, and the beasts called to life a few seconds before retreat below the surface. Thinking he's done a good day's work, the Doctor returns to the TARDIS—only to find out that the planet has sucked it down into its very depths . . .