The Doctor and Rose in “The Parting of the Ways”

Rose Tyler. I was going to take you to so many places. Barcelona. Not the city Barcelona, the planet Barcelona. You'd love it. Fantastic place! They've got dogs with no noses! [Laughs] Imagine how many times a day you end up telling that joke and it's still funny!

Then... why can't we go?

Maybe you will, and maybe I will. But not like this.

You're not making sense.

I might never make sense again! I might have two heads, or no head. Imagine me with no head, ha! And don't say that's an improvement... But it's a bit dodgy, this process. You never know what you're going to end up with. [he gasps as a burst of regenerative energy erupts from his torso]

Doctor!

Stay away!

Doctor, tell me what's going on.

I absorbed all the energy of the time vortex, and no one's meant to do that! [chuckles, but then looks up at her seriously] Every cell in my body's dying.

Can't you do something?

Yeah. I'm doing it now! Time Lords have this little trick. It's sort of a way of cheating death. Except... it means I'm going to change. And I'm not going to see you again. Not like this. Not with this daft old face. And before I go--

Don't say that!

Rose, before I go, I just want to tell you you were fantastic. Absolutely fantastic. And do you know what? So was I! [The Doctor regenerates.]