The Power of Regeneration
The Doctor has survived (sort of) his first encounter with the Cybermen. Instead of using the term regeneration, the Doctor calls his change a 'renewal'. Ben is sceptical, but Polly takes him at his word. However, no rest for the weary as the next adventure takes the Tardis crew to the planet Vulcan, an Earth colony. It isn't long before they run into trouble and a dead body.
The dead person is an examiner from Earth, sent to investigate a dead alien space-craft which has been found on the planet. The Doctor assumes the role of the Examiner to do his own investigation. Sneaking onto the space-craft, the Doctor's hunch is right and he discovers several inanimate Daleks. What makes matters worse is one of the Daleks is missing!
Lesterson is the chief scientist in charge of the space-craft and has been testing one of the Daleks. He believes the Daleks can be used as servants. Things seem to be going according to plan as Lesterson only gives the Dalek partial power and has taken away the Dalek gun. To further convince him, the Dalek assures him he's his servant. The Doctor sees through this and explains to Ben & Polly the Dalek is really the one in charge.
The Doctor continues to warn Lesterson about the Daleks, but his warning falls on deaf ears. Lesterson refuses to believe the Daleks are anything other than what they claim, servants. But the Daleks are no fools, while one of the Daleks continues to claim its servitude the rest of the Daleks have been busy reproducing. Also, they now have enough power stored up to move about freely.
Finally, Lesterson over-hears the Daleks conspiring and finds the assembly line of Daleks. Realizing he has been wrong the entire time, Lesterson goes crazy. He believes fighting the Daleks is futile and they will now be the dominate life form, taking over for homo-sapiens. He also foolishly belies the Daleks won't kill him because he "gave them life".
The Daleks agree he did give them life, then promptly kill him. But the Doctor has used the distraction to use the colonies power to overload the Daleks and blow them up. The Daleks are destroyed, but at the cost of the colonies power supply. The Doctor decides to make a quick exit before he's given the bill for his damages.
NEXT: There Can Be Only One - Or Three