In the Caribbean "Duppy" means ghost - some say it is the lighting caused by the location of the dive site that gives rise to a haunted effect, perhaps it's just the depth of the wall here.

The wall drops deep here, with giant barrel sponges dotted along it. From the buoy you'll find interesting reef formations surrounding a sand patch at 15m(50ft). Follow this sand patch west and you'll find yourself being funneled into a narrow canyon gradually deepening. The canyon will pop you out of the reef wall at around 20m.
Heading the other direction (east) you will find chimneys along the deep wall, looking down you could believe this drop off was bottomless. At about 25m (80ft) you can find a locally famous barrel sponge around 2m(6ft) in size, locally famous amongst divers here because it makes a great navigational reference! Look out for spotted drums, large groupers, and if you are into small stuff hunt around in the shallower reef areas to the east of the buoy to look for cleaning goby, blennies and a variety of creatures!