"Okay. And this living plastic, what's it got against us?" asks Rose, as she and The Doctor loiter about outside the TARDIS, still standing on London Bridge. He says it's got nothing against them at all: "It loves you. You've got such a good planet! Lots of smoke and oil, plenty of toxins and dioxins in the air...perfect. Just what the Nestene Consciousness needs. Its food stock was destroyed in the war, all its protein plants rotted, so Earth: dinner!" Next episode has a similarly eco-friendly bad guy/set of circumstances. Interesting. It makes sense that the immortal Doctor -- who, with nothing better to do, has always tended to focus on Earth and its lovely inhabitants -- would see environmentalism altogether differently from your average. It's hard to make that work without seeming overly sincere, but I think there are only a few really preachy bits, and this isn't one of them. A plastic-based consciousness would for sure love Earth, for all those reasons and more. Hell, Paris Hilton and most of Hollywood already live on dioxins and red dye #3. Well, orange dye at least. Asked whether there's a way to stop it, the Doctor proudly produces a tube of blue liquid from a pocket: "Anti-Plastic!" It is the amazing grin that accompanies this pronouncement that sells it. "Anti-Plastic?" asks Rose. Yes. But first the Doctor's got to find the transmitter that the Consciousness is using to control all the plastic. Rose stands opposite the Doctor, framed by the London Eye, as he explains that it should look like a transmitter, "round and massive, slap bang in the middle of London." He paces, continuing: "A huge circular metal structure, like a dish. Like a wheel. Close to where we're standing." Rose stares at the Eye. "Must be completely invisible," he muses. She nods toward the Eye, and the Doctor turns and looks at it several times without comprehending. He keeps asking her what she's trying to say, and finally it clicks. "Oh. Fantastic!" he grins, and takes off.

Hand in hand, laughing joyfully, Rose and the Doctor run across London Bridge toward the Eye. I like them best when they're like this: wild and happy and just getting on with it. "Think of it," says the Doctor, once they've reached the Eye. "Plastic, all over the world. Every artificial thing waiting to come alive. The shop-window dummies, the phones, the wires, the cables..." Rose nods: "The breast implants..." He shakes that off: "Still, we've found the transmitter. The Consciousness must be somewhere underneath." Rose finds the entrance, and they head into the underground. As usually happens in this sort of story, toward the end.