Aaah, yes, another English country house Christmas ghost story. And again, we have a narrator sharing the story of a spooky encounter.
In “Between the Lights" by E.F. Benson, Everard Chandler experiences something that I suspect most of us have -- he sees something, but he has no idea what it was, or if it was anything. Whatever it is he sees, it's always in shadow, between the lights, living in the space between reality and imagination.
He tries to tell himself that it's only a shadow, but he is haunted by it.
And, that horrifying thing he saw on the croquet lawn, could that really have only been a shadow?