Sentenced to Death

Today at work, the red-haired guy pulled out a sheet of paper with an odd logic puzzle on it that I'd never heard before. I'll try and summarize it as best as I can.

Three men have been sentenced to death and are burried up to their necks in the ground. Man A faces a brick wall. Man B faces the other side of the brick wall. Man C faces the back of Man B's head and Man D faces the back of Man C's head. Man A can only see the wall. Man B can only see the wall. Man C can only see Man B. And Man D can only see Man B and Man C.

Each man wears either a black or white hat. Man A wears a black hat, Man B wears a white hat, Man C wears a black hat, and Man D wears a white hat.



The executioner tells the men that they will all be executed unless one of them can tell what color hat he (the condemned man) is wearing. None of the condemned men can communicate with each other.

One of the men successfully tells the executioner the color of the hat he wears and the four are set free. Which man was able to figure out the color of the hat he wore and how was he able to do it?

I tried to find this logic problem online, but I couldn't. I did find several similar puzzles featuring men wearing different color hats, but they're not quite the same as this one.

I think what interests me most about this puzzle is the bizarre scenario of four men burried up to their necks and threatened with death unless they answer some absurd puzzle. It's like the plot to a future sequel of Saw or some other ultra-violent horror movie.