Have you ever noticed those shadows you see in your peripheral vision? Those split second signs of movement that you just brush off as tricks of the eye? Those are the Witnesses, there's thousands of them.
The Witnesses have always been here and they always will be. Watching, noticing... terminating. They move extremely fast, but if you manage to catch one, listen to it. Hear of its knowledge.
They've been watching for centuries, and they learn.
They know every aspect of human nature, tricks to success, wealth, and fame. Ways in staying healthy and tricks to being able to live long past a human's average life expectancy. They will tell you everything you need to know to live a long and enjoyable life... then they will end yours.
Some secrets aren't meant to be known. So keep brushing those shadows and figures off as just "tricks of the eye". Take it from me, we don't like to be bothered. No, not one bit.