Kinda hard to believe... ahem... Oh! Maybe it's The Aliens you know. You don't see em but they put in their Blue Dye of Domination into your food when you aren't lookin. It's a rare thing to happen to a person, and no defense either except to cover all your windows with tin foil. Otherwise once dominated they can take you up into their ship and experiment on you, and make you have their half/human half/alien babies, who in the future will overcome our world.