Where I am, a chap has taken it upon himself to start a hiking group and we have been on the first two now, I led the second one, yesterday, to help it all get going. I spotted some chaps heading off from the car park before us, with fairly 'professional- looking' camera equipment. That wasn't unusual, as the route is rather scenic, with some picturesque waterfalls, etc.
I was at the front and I, well in front of our group, caught up with them before the waterfalls, where they were clearly setting up for some filming. By this stage, I was aware that there were two women with them, who didn't seem to be directly involved with the technical side.
Being at the front of our group, I felt obliged to warm them of what was following me, so that we didn't blunder through some carefully set up shot.
One of the women looked vaguely familiar and, as I am often in the presence of people that I actually know, but can't place, I addressed my information through her, so that she wouldn't feel that I was ignoring her.
I told them that there would be twentyish following behind me, but they would pass through fairly quickly.
She responded in a way that suggested that she was no surer of who I was than I was of who she was.
The group passed through and, after people had got a few photos, etc, we moved on.
Later in the evening, I saw a post from a local group in the area of the walk which explained what was going on.
This revealed that the woman who looked a bit familiar was actually a well-known TV person here, a sort of Jeremy Paxman/Kate Adie type of fairly hard journalist-interviewer. They were filming for a future episode of an outdoor activities programme and she is from the area.
en.wikipedia.org
I'm sure that my investigations have been more effective and she is still unaware of who I am...