When the TARDIS needs to reset itself, the Doctor, Nyssa and Tegan find themselves having to fill time on a space-hub filled with numerous attractions. This pleases Tegan and Nyssa no end... but the Doctor is more interested in visiting an alien friend of his living on a nearby mining planet and is able to persuade his friends to join him.

But on arrival, his friend is nowhere to be found and the locals are more than slightly unwelcoming. With limited options for departure and a hostile populace they may be in a lot of trouble.

Sometimes true monsters are found in the strangest places.