scenes from a movie dreams

I've had a few dreams where it seems like they're scenes from a movie, but none like I've I've seen and I'm a character. The most interesting one was this old museum that, many years back, used to be a home to a wealthy family. Anyway, in the dream I was standing around a table in one of the rooms with the people who owned the museum and they were dressed up in prairie clothing. Never met the people before in my life! It could actually feel the coldness of the room. The women in the room started to shake and whimper. Then for some reason one young woman opened the double window and flung herself out, towards the ground below. The museum/home was at least 3 stories. I remember yelling "No!" I couldn't move, nobody could or chose not to, to catch her. After that it was like my mind jumped scenes, because next I started seeing the town on fire! Young adults and teenagers, some of them drunk, were rioting in the streets. Burning everything in site! Except the museum. My mind then jumped to a new scene where I was sitting in old automobile with three other people. Two were from employees at the museum, but the other I didn't recognize. Anyway we were being chased by another car. The girl beside me was really freaking out yelling, "He's insane! Truely insane!" I didn't know who she was talking about but I woke up after that. What does all that mean and why did I dream it?