Who’s that person in the drivers seat?

I am doing some urban spelunking with three friends of mine. We go to several run down houses and walk around in them in the dark. We use our flashlights to look at some interesting things. One of the four of us is the main tour guide. He shows us things in the buildings and speaks about them like he was on a TV show.

In the last house, we go up to the second floor to look at things. As we climb down a ladder to leave the building, I see another person climbing down another ladder. I catch him out of the corner of my light. On the lower level we have to walk through long sheets of plastic to get to our car. Me and a woman who I am with get into the back seat, and the tour guide comes around on the shot gun side of the car. He looks at the man who is at the wheel and asks, “Who’s that person in the drivers seat?”

Before we can react, the stranger starts the car and quickly drives off.  I frantically think of many things at once: where’s the person that was with us, should I jump out of the car without the woman, should I attack the driver, who is the driver?