Discuss photo: " Ghostly" spectre

If anyone's interested in the photo. I'll gladly e-mail it to you. It's taken with a digital camera.
The location is the underground caverns in Valkenburg, the Netherlands. Loads of history

So, to explain whats going on here you have to first understand several complex factors taking place.

In this picture you have several components going on, #1 motion blur. You've got a moving camera which in the near field is fairly sharp but on the more distant areas you can see a bit of motion blur going on. Second, you've got front and back lighting, but the back lighting (from the flash) is very intense. And its casting a very distinct shadow just in front of each of the subjects. You can see it best on the back of the jacket of the person who is farthest away. You can see the distinct shadow outline of the person in the blue/white shirt. Further more that person is also casting a shadow against the bottom of the right railing. Farther down you can see the red amber back lighting from the lighting in the passageway. This in some areas is overriding the shadows. When you zoom in on the area in question, it becomes much clearer that what we're seeing is simply shadow play from the multiple light sources.

the tunnel looks crazy I would love to tour that also, the image to me looks like rocks lite up ,,but if I look real fast the rock looks like a head but a blurry one,,good one, I like Crystalsross version more explainable..