"This?" he asked, nodding toward the screwdriver, "it's a multi-purpose sonic device!" he explained, glaring at the vampires in a threatening manner, who like the others he had encountered seemed wary of the unknown tool. "Basically the only interesting thing about it is a little something I discovered by accident..." he went on, even though it seemed completely irrelevant and rather foolish.
He was quickly distracted from whatever he was going to say as the stranger retorted to his question in a most unusual manner. The Doctor stopped short and looked at him in amusement before giving a short laugh. "OK then..." he said, drawing out the syllables as if the other man were the crazy one.
His amusement was cut short once more as the situation seemed to violently escalate. "Oh. Wait. I was saying something. Yeah, the interesting thing about the sonic device is that it's bloody useless!" he said quite loudly, causing the vampires to laugh cruelly as they made a move to attack. The Doctor pressed the screwdriver into action, offering nothing but a small blue light and a sound akin to TV static. As before, the vampires clutched at their heads, temporarily disorientated. "Except for that. What's that all about?!" he asked the stranger as if he'd have any sort of response to such a ridiculous question. "Guess there's just no talking civilly with some people," he mused with a slight sigh. "Sorry, what were you saying? Somewhere to go. Well, we could hide in that blue box over there until they go away, yeah?" he grinned, starting to lead the way back to the TARDIS.