Doc Savage: The Sinister Shadow

I couldn't find any information about the book being a study guide. Based on the title and publisher, I would categorize it as a work of fiction. Here's a revised product description:

Doc Savage: The Sinister Shadow by Lester Dent is a classic pulp adventure novel featuring the iconic hero Doc Savage. This paperback edition is published by Altus Press, a leading publisher of vintage pulp fiction. The book is a thrilling tale of mystery and action.