 Works with grass, foliage, sand and sky. And if you look at some of the videos online about it, it's like they put up this, I guess, panel in front of people and then they truly do disappear. I know that every Harry Potter fan would want one of these right now. But speaking of being invisible, here's a joke that you can tell the kids. How did the doctor cure the invisible man? How did the doctor cure the invisible man?