Genesis of the Daleks  -  Doctor: Do I have the right? Simply touch one wire against the other, and it’s it. The Daleks cease to exist. Hundreds of millions of people, thousands of generations, can live without fear, in peace, and never even know the word “Dalek”. Sarah: Then why wait? If it was a disease or some sort of bacteria you were destroying, you wouldn’t hesitate! Doctor: But if I kill, wipe out a whole intelligent life form, then I’d become like them. I’d be no better than the Daleks.

“Are you or aren’t you?”

The Time Warrior - season 11 - 1974

“I can’t switch it off!”

Pyramids of Mars - season 13 - 1975

“That takes us to just about the end of the 20th century.”

The Masque of Mandragora - season 14 - 1976

“I don’t like the look of them.”

The Android Invasion - season 13 - 1975