Some people believe there's been Aliens in or on our planet since millenia,it's just...we can't see them...partly because they're not on our plane of existence or dimension,partly because they're hiding from us.Only the military and some politicians have contect with them Aliens,of which some are been kept below ground somewhere in the U.S.
Would'nt astonish me at all if it were true with all 'em creeps walking around there...
