How Did NCIS Inspire Mark Harmon to Write a Book After Leaving as Gibbs, and What’s the Story Behind It?

Mark Harmon, known for his iconic role as Leroy Jethro Gibbs on the long-running television series “NCIS,” has embarked on a new endeavor – co-authoring a book. This book, titled “Ghosts of Honolulu: A Japanese Spy, A Japanese American Spy Hunter, and the Untold Story of Pearl Harbor,” is a nonfiction work centered on the history of the Office of Naval Intelligence, which preceded the Naval Criminal Investigative Service (NCIS). Harmon co-wrote the book with Leon Carroll, Jr., a former NCIS agent and technical advisor on the show.

In a statement, Mark Harmon expressed his motivation for sharing this untold story, saying that he felt compelled to help uncover the history and real story behind the establishment of NCIS. When he began working on “NCIS,” there was limited information available for research. The book delves into the historical events of World War II, particularly the story of Takeo Yoshikawa, a Japanese spy who gathered intelligence on the American fleet in Pearl Harbor, and Douglas Wada, the sole Japanese American operative in naval intelligence.

Harmon’s co-author, Leon Carroll Jr., explained that the book offers readers a fresh perspective on NCIS as an agency, moving beyond the typical homicide investigations. “Ghosts of Honolulu” is intended to be the first in a series providing an inside look into the inner workings of NCIS. The book is scheduled for release in November.

As Mark Harmon continues his involvement with NCIS as an executive producer, the possibility of his return to the show as Leroy Jethro Gibbs remains uncertain. In the meantime, fans of both Mark Harmon and NCIS can look forward to his upcoming nonfiction book that delves into the history of the agency. The book’s release coincides with the 20th anniversary of the original NCIS series, which debuted in the autumn of 2003. While Harmon’s portrayal of Gibbs in “NCIS” is undoubtedly his most iconic role, his new role as a published nonfiction author is an exciting addition to his list of achievements.