“Aliens exist.  There are different species fighting each other for the right to control this planet and most humans have no clue about what’s going on.  For those innocent humans who are abducted, they are used as lab rats, having implants put in them without their knowledge.”
“There are a handful of rebel humans who know the truth.  We fight the aliens where we can, but it’s not easy.  They have the power to paralyze us, taking pieces of us while we sleep, or outright killing us.  I know all of this because I am one of those warriors, and they found me last night.”
“It was like any other night.  I got in bed, pulling the covers over me tightly.  My heater is not working properly so I was trying to get as warm as possible on my own.  It was not long before I passed out.  When I woke up, my blanket was missing, my bedspread had small traces of blood and there was a round scab on my right calf about an inch round.”
“The scab was black and hard, as if it had been on my leg for weeks, not hours.  I began to peel the scab off slowly and to my surprise it came off in one piece, almost like a band aid.  I could see that the hole went about a quarter of an inch deep, give or take, and was cone shape.  It looked like someone had removed the calf meat surgically.  It was too perfectly round.”
“Uh, why are you telling me all of this?”
“I’m just trying to explain why I’m not coming into work this morning.  Duh!”