House of 1000 Corpses ending explained (spoilers)

[claude]

The last surviving girl escapes from The Professor (the big guy with the axe) and crawls out of a hole in the ground that leads to the outside world. Captain Spaulding is driving down the road in his convertible, sees the girl, and picks her up. He says that there are a whole bunch of people looking for her and says that he'll take her to a doctor. She lays her head back and starts to fall asleep, but Otis rises out of the backseat. It then changes to a scene where the girl is back in the mental institution beinh operated on by Doctor Satan.