I used to skate with a guy who turned into a mean junkie. He was really into aliens and flying saucers and shit. He claimed that he and a bunch of people we went to school with saw a UFO one night, but when he brought it up with them they all told him that they had no idea what he was talking about.
A few years before his junkification, we took some magic mushrooms and went adventuring through a marsh. Once we were done being groundlings, we rolled some joints and got ready to walk home. We posted up on a bench near a river and smoked the first joint. About halfway through, the dude gets my attention and points to something in the sky. It was a bright light over the horizon, and it was moving in a straight horizontal line.
"Oh word, it's a helicopter," I said. Then it stopped on a dime, hovered for a bit, and descended out of sight. He freaked out and insisted we saw a UFO. I told him I thought it was a helicopter, but he was adamant that it was a UFO. After that, he would bring it up about once a month, just to see if I remembered that time we "saw the UFO."
Since then, our friendship dissolved and I cut ties with him after he called my girl an Amazonian. But if I ever run into him and he asks me about that time we saw a UFO, I'm going to tell him I have no idea what he's talking about.