Based on the title *Operation Führerhauptquartier* and information about the author **Will Berthold**, here are some themes and topics that could help you connect this book to others in a library:
* **World War II**: This is a central theme, given the book's title referencing Hitler's headquarters. You can connect it to other WWII fiction and non-fiction books.【1】
* **German Resistance**: The book may relate to the July 20, 1944, plot to assassinate Hitler, providing a connection to books about the German resistance movement.【2】【3】
* **Coup Attempts**: The narrative involves a coup attempt, which can link it to books on military history, political intrigue, and failed revolutions.【3】
* **Espionage**: The plot involves English agents trying to eliminate Adolf Hitler, suggesting a theme of espionage and covert operations.【4】
* **Historical Fiction**: Will Berthold was a writer of both fiction and non-fiction, with a focus on crime and the Second World War. This book could be categorized as historical fiction.【1】
* **Coping with the Past**: The book may explore the theme of Germans coming to terms with their history during and after the Nazi regime.【2】