Recap: Doctor Who S4 E3 "The Power of the Daleks"

Headless Daleks? Clearly there's a rogue model running around, trying to be the only one...
"The day had started badly. In the console room aboard the TARDIS lay a disorientated body ragged with pain. It was me, in an earlier regenerative form. It was also the time of my first regeneration, the event that is both a blessing and a scourge of the Time Lords of Gallifrey. Some Time Lords are able to proceed through their allotted twelve lives with grace, dignity, and alan; growing older, wiser, and more handsome with each change. Others are less fortunate, as my first metamorphosis proved: One moment a distinguished, white-haired gentleman, and the next, well, not what I would have wished for myself, but at least I was alive. Just."
The Doctor, the novelization of the episode

The Doctor: Life depends on change, and renewal.
Ben: Oh, that's it, you've been renewed, have you?
The Doctor: Renewed? Have I? That's it, I've been renewed. It's part of the TARDIS. Without it I couldn't survive.

Arguably one of the most important Doctor Who stories ever madenote , The Power of the Daleks had to establish that a new actor could take over the lead role and play the Doctor completely differently, yet still remain true to the character.

The Doctor has changed. Ben and Polly discuss what's happened. Ben does not believe this stranger could possibly be the Doctor, while Polly thinks it must be him, reasoning that they've seen many impossible things recently. It doesn't help when the man continues to refer to "The Doctor" in the third person.

The TARDIS lands on the planet Vulcan, the site of a future Earth colony, and the Doctor goes out to explore with Ben and Polly following him. The Doctor has hardly set foot on the planet when he witnesses a murder and, on examining the body, discovers a pass proclaiming the dead man to be an Earth Examiner. Attacked from behind, then rescued by people from the colony, the Doctor decides to impersonate the dead Examiner and investigate. He discovers that there is a rebel movement bent on overthrowing the governor, but also that there is a far more dangerous problem in the form of a crashed space capsule containing inactive Daleks.

Despite the Doctor's warnings, the Daleks are activated and present themselves as willing servant robots, taking advantage of the colonists' trust to set up a reproduction plant. Meanwhile, internal power politics in the colony sees Security Chief Bragen secretly leading the rebels as a way of deposing Governor Hensell and seizing power for himself, while Deputy Governor Quinn has been locked up. Bragen believes the Daleks will help him and has rearmed them.

Of course it's only a matter of time before the Daleks are strong and numerous enough to emerge from their capsule and go on a killing spree. Many colonists are killed before the Doctor uses the colony's power supply to overload and destroy the Daleks.

Ben concedes that this probably is the Doctor after all, and the three depart for adventures new.

This story only survives in total in an audio format, thanks to fans at the time tape-recording it. There are a few short visual clips composed of extracts used in other programs and short clips made by pointing a camera at the television during transmission, as well as a partial trailer for the story. The few minutes of existing material can be found on the "Lost in Time" DVD set.