The Doctor: There's only one thing for me to do, Mike. I've got to go after her to Metebelis III.
Mike: In the TARDIS?
The Doctor: Yes, of course.
Mike: But how can you be sure you'll get there?
The Doctor: The TARDIS may be a little erratic, I'll admit. But Metebelis III is the one planet I'm absolutely certain of reaching. I wired the coordinates into the programmer.
Mike: But Doctor, a planet's a big place.
The Doctor: Yes, well, I always leave the actual landing to the TARDIS herself. She's no fool you know.
Mike: You speak as if she were alive.
Doctor [ smiling ]: Yes. Yes I do, don't I?