to wonder what they are doing

[sashh]

It's 4am
I live on a cul-de-sac
There is a car I don't recognise parked across from me
There are people in it

AIBU to wonder what the hell they are doing at this time in the morning?

• casing the houses to see which one's worth breaking into
• enjoying a quiet moment somewhere reasonably deserted after a date (not necessarily anyone who lives there, just a couple looking for privacy who for whatever reason can't get it at home)
• drugs dealing
• lost and looking at a map
• seeing what the area is like in the early hours as they're considering moving there
• chatting after a night out where someone has given someone else a lift home

How many more random possible explanations would you like? :)

Orgy.

Car orgy.

Knock on the window and offer them a cup of tea and some digestives.

The car's driven off now, there were definitely two people in earlier but it looked like just the driver.

Who ever it was didn't put the lights on so Vix one of your explanations might be right.

Scum that was my first thought