Terminator: The Sarah Connor Chronicles, Season 2

Cameron:
I think I'm a machine.

Rita:
A machine? What kind of machine?

Cameron:
From the future.

Rita:
What do you do in the future?

Cameron:
I'm an infiltrator.

Rita:
What do you infiltrate?

Cameron:
The human resistance.

Rita:
I see. Why?

Cameron:
It's what I was programmed for.

Rita:
Programmed?

Cameron:
To find John Connor.

Rita:
Why is he so important?

Cameron:
He's the one who saves mankind.

Rita:
Saves them? From what?

Cameron:
Extinction.

Rita:
And what are you going do when you find John Connor?

Cameron:
I'm going to kill him, and hang his head from a pike for all to see.