When I was out with my first boyfriend, we used to go out to the park after dark.
Once we were walking across the bowling green. Right in front of us there was a little old man, maybe in his 80s. As he walked towards us, he asked what time it was. I looked at my watch, and told him it was ten to midnight. He walked past us, and I commented there was nowhere somebody could have come from.
We looked round, and he was gone! There was no way somebody his age could have sprinted over to the pavilion out of sight. We ran out of the park and didn't go back there again!