A hidden figure?

From The Spiral Staircase (dir. Robert Siodmak, 1946). Blanche (Rhonda Fleming) has gone to the basement to fetch her suitcase. I can’t decide if the vaguely human form at the center of the screen is meant to suggest a person, lurking, or not. All I know is that it scared the bejesus out of me. The form turns into a pitcher and some shelving with a bit more light. Click any image for a larger view.

[Now you see it.]

[Now you don’t.]

[In case you missed it.]