Life is about to change for the pacifist dulcians when the dominators, self-acclaimed masters of the ten galaxies, arrive on planet dulkis. The Doctor (Patrick Troughton) is intending to take a peaceful holiday on the planet Dulkis, but the Quark robots have other ideas. The main villain in this story is the Dominator Rago. Patrick Troughton is good and the action is reasonable including a plan to turn Dulkis into a radioactive source of power..