The Daleks planned to invade a planet. The First Doctor and Ian Chesterton found themselves on this planet and encountered the Daleks.

In order to defend themselves, the Doctor and Ian developed a ray gun. When a group of Daleks found them, Ian fired the gun at a Dalek called DK3, destroying him. Realising that the planet was not defenceless, the Daleks evacuated. (COMIC: The Defeat of the Daleks)