Here's the nightmare scenario. You stop by your elderly mother's house to check on her. You grab the doorknob. It's hot to the touch. You ring the bell and knock. No answer.

You fish out your key and open the door. You call out but there's only silence.

The air is warm. There's a sweet, smoky smell. But, nothing looks out of place.

Finally, you go into the living room and you see it.

In your mom's favorite chair, is a pile of smoldering ash. Completely unrecognizable as human.

Just as you convince yourself that this isn't your mother, you see her jewelry in the gray dust.

And then the grisly sight of your mother's feet, still in their slippers, on the floor by the ashes.

There was a fire. An intense fire. But aside from her chair, nothing is burned. Even stranger, everything in the house is covered with a thin layer of pale yellow grease.

Your mother was a victim of spontaneous human combustion. Though rare, it happens more often than you think.

According to at least one scientist, it could happen to anybody at any time — even you.