A Quiet Exchange

The clouds began gathering over the mountains today in early affirmation of the forecast of wind and rain for Christmas and Boxing Day. When I crouched on the breakwater to face north and snap this blip I didn't notice the surreptitious transaction taking place below me on the beach. It wasn't until I examined the photograph later than I noticed it. Quite innocent, perhaps. But there seems something a little clandestine about it. Anyone any ideas about what might have been going on?

Happy Christmas, by the way!