They started appearing that afternoon, complex circular marks in the grass, on the concrete and asphalt, everywhere, just like the old guy said. The government went and fished him out of the looney bin and started asking him hard questions. Soon he was on the news.
“They're just graffiti. You know, like the kids do. Tagging. ‘I was here’, and so on. Each design indicates a particular individual. That’s why some repeat: some of them have visited multiple times.”
“But what to they want?” Asked the host.
“Oh, just blowing off steam. Probably won’t do much damage. You know kids.”