The Movellans outwardly resembled physically attractive Humans of various ethnicities and both genders. All of the Movellan androids wore white, form-fitting uniforms and their hair in silver braids. Being androids, the Movellans were strong and tough. The major weakness of the Movellan design was each android's external power pack which, being, carried on their belts, was easily removed and completely shut down the android. The power pack circuitry could also be modified, reprogramming the android to obey human orders.
The standard Movellan sidearm was a small, hand-held weapon. The weapon had both "kill" and "stun" settings.
Romana identified the Movellans' ship as being from star system 4-X-Alpha-4.
It was claimed by the Dalek Prime that the Movellans were actually the creation of the Daleks and that the war was a fake created as part of an elaborate plan to prevent the destruction of Skaro as recorded in their history.
Another account claims that the Movellans and the Daleks encountered each other while both sides were expanding their interstellar empires beyond the bounds of the galaxy and immediately engaged in a war which lasted for centuries. As the empire's respective warfleets were evenly matched, neither side's purely logical battle computers could find a successful strategy for an attack against the other and so the two fleets remained locked in a stalemate, constantly manoeuvering and probing for weakness but never actually firing a single shot.
The Daleks returned to their homeworld, Skaro, to retrieve and revive their creator Davros, hoping that he could find a way to break the impasse, and the Movellans sent their own expedition to stop them. Davros determined that the first side to take a seemingly reckless gamble would be able to gain the advantage, but the Doctor prevented either side from returning to their respective fleets with this insight.
About ninety years later, the Movellans developed a biological agent which attacked and was almost instantly fatal to the physiology of the mutant within the Dalek shell. They used this to win the war. The once-great empire was reduced to a few scattered colonies. Once more, they sought out Davros for assistance. By this time, Davros resided in cryogenic suspension in a space station. The plan went wrong both as a result of Davros himself turned against the Supreme Dalek as well as the involvement of the Doctor.
What happened to the Movellans after the war has never been established on-screen. However, it is widely believed that they were eventually defeated and destroyed by the Earth Empire.