Beneath Paris there are hundreds of old tunnels that were once a limestone mine. Later, in the 18th century, the cemeteries in Paris became so overstocked with corpses that the bodies would no longer decompose. The stench and disease forced the government to empty the cemeteries. The human remains had to be put somewhere so it was decided that they would be placed in the catacombs. As if the dark, dusty tunnels of the catacombs weren't creepy enough, now the floors are littered with the bones of thousands of people.
The Catacombs are almost entirely unmapped. Because of this, and of the fact that no sunlight reaches the tunnels and many areas have collapsed they have now been sealed off from the public. This doesn't stop groups of people, cataphiles they're called, from sneaking down into the tunnels and exploring.
A few years ago one group of cataphiles found a miniDV camcorder mysteriously abandoned in one of the tunnels. The video the camera captured is chilling. It may very well be a man videotaping his own death.
I think the video is authentic and not some high-concept prank. Who would waste a perfectly good miniDV camera (which were much more expensive years ago) for a gag that may not even pay off if no one finds the camera or if the tape gets destroyed by rain water?