Commander X: "Dulce Base's Nightmare Hall is where aliens perform sick experiments on humans!"

Forget Area 51, the most terrifying alien conspiracy theories focus on a US military base so secret that its existence hasn't even been officially confirmed - Dulce Base.
The mysterious base is an underground facility in the middle of the New Mexico desert, said to be manned by aliens who carry out extreme experiments on abductees, including the creation of freakish extra-terrestrial-human hybrids.