A dark night, naturally. Could be funny, if it was a city that could take a joke. It was a place where a joke literally bombed. It was a place where a joke was more likely to take a life than raise a laugh. And the laugh was never a good sign.
A siren. Movements in the alleys. Work to be done.

"Oh, no, no, NO!"
Of course the TARDIS was malfunctioning, bless her, she was always malfunctioning. It had got to the point that it was a surprise if she didn't start exploding every couple of days (to the extent that days could be used as a measurement of time within the vortex). It wasn't even a surprise that everything was going hazy, or that the contents of the TARDIS library seemed to be rapidly filling up the control room. But it didn't mean it wasn't irritating.
"Come on, girl, not today. It's just an easy trip, Eye of Orion straight through to Greenwich. You don't need to take a detour through Crazytown!"
Not that she ever listened. She didn't do what she was told, she did what she needed to do. And it was still really, bloody irritating.
"I mean, don't I get a break? I've hardly recovered from those vampires, and that was already following right on from the horse thing... not to mention Tenerife."
Eugh.
"I don't know what the appeal is. It's so boring. Just lots of sleeping, and sitting around, and talking to such stupid people..."
Not that it was an issue now, what with the doors flying open and unleashing a sea of red and blue, swishing back and forth through the TARDIS.
"It's in my hair! It's in my girly hair!"

The cops would find them eventually. Nothing more serious than a fractured limb between them, but they wouldn't be trying anything else for a while. Their almost victim would probably be more careful in future too – from the look on his face as he ran away, he wasn't going out at night again.
The flash of blue in the alley signalled the arrival of the authorities. Time to move on. That whirring sound would be a good next stop. In a city like this, it could only be danger.

"Urgh..."
Ok. Lights off. Doors wide open, giving a good view of the night sky. Lots of timey-wimeiness floating around. A distinct taste of purple. It was one of those landings.
"Where are we... this time?"
The continued presence of breathable air seemed to be a good sign, although that usually meant more air for monsters and bad guys to breathe. Probably chasey bad guys, too. The sort who would bust through a door and ram straight through the hastily yet precisely laid trap behind it without flinching, take a whole room in one jump and be on you before you could reach the hallway. They were the worst. Well, the worst of the mindless hunters, anyway. It could get much worse than that.
"It's Earth, right? I bet it's Earth."
Because Earth meant a whole host of villains, ranging from the spineless quislings to the maniacal leaders and master planners. Sometimes they managed all three, which tended to seem like overkill, but a careful balance could be surprisingly effective in the right hands. Then again, anyone who could be described with a word like 'maniacal' was almost certainly the wrong hands.
"You still there, old girl?"
Nothing. The control room was dark, visible only from the light coming through that persistently open door. It was a good excuse, having the TARDIS unusable until the nearest threat could be resolved, but it wasn't good for her to act so recklessly in flight. As anyone worth listening to knew, the taste of purple was never a sign of good health in a time machine. Still, she'd probably be fine within the hour. Maybe less. For now, all there was to do was to climb out the door (a strange experience, given the interior's staunch insistence that it was the right way up) and take a look around. Meet the locals, find out if anything strange had been happening...
"Alright, buddy, we both know how this is gonna go down. Turn around, and no sudden movements."
...and run straight into a representative of the city's criminal underside. Fantastic.