DOA's Answer Key for the October 17, 2021 Literary Rebus

 

The granite was cold and rough against the gray cloaked man’s palms. It was good, solid granite, from the bones of the earth itself. He traced barely perceptible seams between the huge blocks of the wall. It was the seams, he believed, that held the key. The key to the wall’s destruction.

 

From Green Rider by Kristen Britain