Mickey and Sarah Jane put K-9 back into the car. Mickey asks, you know, what the deal is with the tin dog. "The Doctor likes traveling with an entourage," Sarah Jane tells him. "Sometimes they're humans, sometimes they're aliens, and sometimes...they're tin dogs." Mickey smiles. "What about you? Where do you fit in the picture?" she asks. High on his computer skills, Mickey almost pounds his chest. "Me? I'm their Man in Havana!" (Graham Greene rocks your ass!) "I'm the technical support, I'm...Oh, my God. I'm the tin dog." He sits down in shock and the usefulness of analysis; Sarah Jane grins and pats him on the shoulder and doesn't mention Adric. (Send me an email about how they never met, and see what you get. Sometimes they're just jokes.)
The Krillitane on the rooftop screeches, Finch silences it and tells it to wait as the Doctor and Rose leave the chip shop. "How many of us have there been, traveling with you?" Rose asks. (Do not ever ask this question.) "Does it matter?" the Doctor asks in response, which hurts. One writes, that "Other friends remain," That "Loss is common to the race"? And common is the commonplace, And vacant chaff well meant for grain. "Yeah, it does, if I'm just the latest in a long line," says Rose. The Doctor stops and looks her in the eye, angrier and more than matching her hurt: "As opposed to what?" Rose begins to mumble: "I thought you and me were...But I obviously got it wrong. I've been to the year five billion, right, but this...now, this is really seeing the future. You just leave us behind." And vice versa. The Doctor's a God of Loneliness, not second chances. "Is that what you're going to do to me?" asks Rose. And the Doctor answers her well more sharply than he has any right to: "-- No. Not to you." Everything wrong and bad comes from this tiny little statement, in the fullness of time: the evil in thinking that you can prolong the moment of the sunrise, stretch it out so horribly, just because you're scared of being alone. It reverberates back to the Bad Wolf, and on into Doomsday: it's not that Rose forgot the Doctor wasn't human. It's him doing that. He talks like her now.
"But Sarah Jane, you were that close to her once, and now...you never even mention her. Why not?" The secret he can't tell, the Doctor tells: "I don't age. I regenerate. But humans decay. You wither and you die. Imagine watching that happen to someone who you..." And you best believe he bites that off with a quickness. But Rose is clever: "What, Doctor?" He stares and tries to will her into understanding; tries to crawl inside her mind and heart so that he won't have to speak it aloud. (And if he could do that, it would be love, wouldn't it? A lifetime of knowing in a single moment? Shipper apocalypse next week!) No go. "You can spend the rest of your life with me," the Doctor tells Rose. Her eyes fill with love, and tears. "...But I can't spend the rest of mine with you." The secret he can't tell: that every sunrise contains the sunset, and every song from the TARDIS ends in unconsciousness and the uniform of a lunch lady. That his loneliness is eternal, that immortality reverses the values in the physics and math of people, and makes mortal lives more beautiful, for ending. He's not half as dumb as he lets on. He builds walls inside. "I have to live on. Alone. That's the curse of the Time Lords." So could all the Companions please stop bitching and moaning? He burns all the time. There's no standard for comparison. If the experience of divinity is one that's designed to fade, if the ramp up to the Bad Wolf has to lead back down or else the experience loses all meaning, then what's lonelier than God?