The Doctor and Rose find themselves on a desolate world, in the orbit of a black hole. Trapped with an Earth expedition and the mysterious Ood, the time-travellers face an even greater danger, as something ancient beneath the planet's surface begins to awake.

One of the Ood passes a member of the sanctuary base a box of possessions belonging to the late Captain Walker. He takes them and seals the box but reopens it when the lights dim and the computers begin to claim that “he shall awake”. He takes out a book containing a series of ancient symbols and as he looks the computers around him go mad, spouting that “the beast is awake and he shall rise from the pit”. Doors begin to lock themselves and the book bursts into flames, reducing itself into dust. The young man tries to open a nearby door but it is locked tight, and all it can do is tell him the “he is coming…” Some time later the young man sits in a swivel chair in the returned-to-normal room. A young woman enters and tries to talk to him but gets no reply. She turns his chair around to find him lifeless; a series of the ancient symbols etched to his skin…