Doctor Who/Recap/S4/E03 The Power of the Daleks

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 made, 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 TARDIS arrives on the planet Vulcan, an Earth colony in the future, and the Doctor leaves to investigate. Polly and Ben follow him, Ben sceptical about the regeneration and believing that the new man is an impostor.

Meanwhile, 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. Using the pass for himself, he enters the colony where he discovers that there is a rebel movement in progress, and that the colony's scientists have found 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. He believes the Daleks will help him and has rearmed them.

Once the Daleks show their hand (sucker?), Bragen and Hensell are both 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. The few minutes of existing material can be found on the "Lost in Time" DVD set.

Tropes

Accidental Aesop: Those who forget history are doomed to repeat it—unless the Doctor arrives in time.
Armor-Piercing Question: A Dalek in a philosophical mood: "Why do human beings kill other human beings?" Ouch.
Circular Drive: One of the few surviving clips from the story shows the three Dalek props representing an army in this way.
Civilian Villain: "I AM YOUR SER-VANT!" And if you believe that, the nice man in the wheelchair has a timeshare on Skaro you can invest in...
Death By Genre Savvy: Resno realizes something isn't right with the Daleks and says so. He promptly gets "accidentally" zapped for his troubles.
Genre Blind: The colonists.
Go Mad from the Revelation: When Lesterson sneaks into the capsule and sees the Dalek reproduction factory, he has an epic Freak-Out that eventually drives him to willingly take a Dalek Death Ray to the face.
High Heel Face Turn: Janley, for reasons of self-preservation as much as anything else.
Ironic Echo: After Lesterson snaps.

Lesterson: I am your servant.

Just Think of the Potential: Lesterson begins fiddling with the spaceship because the alloys it contains are remarkably resistant to damage and wear.
Large Ham: Lesterson starts out a bit histrionic and by the end of the story has gone so far over the top he's somewhere in high orbit.
Missing Episode
Name's the Same: No, not that planet Vulcan.
The Nth Doctor: Duh.
Only Sane Man: The Doctor has a hell of a time convincing the colonists that their new friendly robot buddies are not as nice as they think.
Out-Gambitted
The Radio Dies First
The Starscream: Bragen.
The X of Y