Then I saw the shadow. It was the shadow of a man with a hat on. At first I thought it was a tree, but there was no wind blowing, and tree trunks never walked. The back porch was bathed in moonlight, And the shadow, crisp and toast, moved across the porch towards Jem.
Dill saw it next. He put his hands to his face.
When it crossed Jem, Jem saw it. He put his arms over his head and went rigid.

– Harper Lee

To Kill a Mockingbird, Chapter 6. Scout joins Jem and Dill to invade the Radley yard at night and get a sneak look at Boo Radley through a window. When the shadow of a man walks past they get the fright of their lives and flee. Not a minute too soon, as Nathan Radley then fires off his shotgun into the air.