She looks at him, her eyes wide and aghast with a strange mixture of wonderment and horror.
He smiles. He loves this look, revels in it, lives for it and breathes for it. Twiddling a few knobs on the circular control panel, flipping a switch, and ultimately kicking the tangle of wires underneath—lovingly, of course, sometimes the old girl just needs a bit more encouragement—he takes them even closer to the expanding star.
The fires of the supernova now cascade around them in a burst of energy and light, the blue box pitching and tossing on the current, a child's plaything caught in a turbulent bath. He can't contain himself, lets out an exultant whoop, a "Hang on tight!" and it is all she can do to hold on for dear life, screaming, terrified. Altogether exhilarated.
The TARDIS jerks violently upward—she's had enough of this for one day, poor thing—throwing the man, this strange and wonderful Doctor, into the arms of the woman, still struggling for breath. He's laughing, a childlike delight all over his face, sparkling and concentrated in those old, old eyes.
"Well?" he says, withdrawing from the sudden but familiar embrace, straightening his jacket, mussing his hair with one hand.
"I told you no!" is all she can manage, still breathless, gasping, leaning against the wall for support, one hand pressed to her thrumming heart, curly blonde-brown hair all undone. "'Supernova surfing'… Honestly. Are you mad?"
"Oh come on," he pries, all smugness and charm and that exuberant smile.
She meets his eyes, still flushed with sublime excitement, adrenalined blood still hot in her veins. A smile creeps slowly across her full lips, making the twin hearts in his chest beat five-and-a-half clicks faster.
"Let's go again."