Following his announcement of retirement as one of the most fearless agents in the Naval Criminal Investigation Service, fans have been eager to see what Mark Harmon would do next, both outside of NCIS and with his first endeavor after leaving the CBS series.
The major case response team of the Naval Criminal Investigation Service, the main federal law enforcement organization for the US Navy, which looks into criminal activity involving the Navy, USMC, and their families, is the subject of CBS’ police procedural drama NCIS. From Seasons 1 through 19, Harmon portrayed Leroy Jethro Gibbs, a Supervisory Special Agent of the NCIS.
After nearly two decades, he quit the series in 2021. In a featurette for NCIS Season 19, Harmon stated, “The character I play and the need to keep it fresh and challenging is what has always drawn me here.” From a plot point of view, this character has chosen its course. I found it to be sincere and acceptable.
Fans of NCIS have been curious about Harmon’s whereabouts and future plans since he left the show and retired as Agent Gibbs. After leaving NCIS, what is Mark Harmon doing next? See how the lessons he acquired over nearly two decades as a fake NCIS agent are applied to his current project.
What is Mark Harmon doing next after NCIS?
After NCIS, what is Mark Harmon doing next? Harmon, who portrayed NCIS Supervisory Special Agent Leroy Jethro Gibbs from Season 1 to Season 19, announced his first project after leaving the show a year later: a book he co-wrote with NCIS technical advisor Leon Carroll Jr. called Ghosts of Honolulu: A Japanese Spy, A Japanese American Spy Hunter, and the Untold Story of Pearl Harbor.
The book, which will be released on November 14, 2023, and is inspired by Harmon and Carroll Jr.’s experiences on NCIS, is a historical account of the Japanese and American intelligence agents in World War II. “These are the real stories from those who were there,” Harmon told People. “It’s real and it’s our history.” The book’s publisher also described it as a nonfiction work that highlights on “the incredible high stakes game of naval intelligence.”
In an interview with People in November 2023, Harmon explained why he wanted to write a book after leaving NCIS. “I left the show, I didn’t retire,” Harmon said. He continued, “I’ve always thought you can learn from history. Things tend to repeat themselves.”
He went on to describe the book. “This is the first story (leading) to the birth of what became (the real) NCIS. These agents are really a different breed. I hope that there’s a story revealed here that you don’t know. It was important work they were doing, and no one knew about it.”
In addition, Harmon disclosed to People that he intended to write a book with the extra time he now has since wrapping up NCIS production. He remarked, “I always find things to do.” To be honest, I think that for the longest period I was just exhausted. Every week I had a lot of stuff to do. I took it quite seriously, and I was not alone in that regard. I miss the friendly banter, the lunches at the tables, and the gossip about people’s lives outside of the show. But it’s a job.” He continued, “I’ve got time to do whatever I want to. I can plan a dinner with the boys, we can take a trip. I’m so fortunate, I don’t ever wake up not thinking that.”
In Ghosts of Honolulu, Harmon and Carroll write about Douglas Wada, the first Japanese American Office of Naval Intelligence (ONI) agent, and Takeo Yoshikawa, a Japanese spy assigned to collection information on the United States — two men had important roles in the “world-changing cat and mouse games” between the Japanese and United States military agents in Hawaii before World War II. “He was a very specific guy in a very specific time,” Harmon described Wada to People.
The book also details the moral conflicts faced by many Japanese American officers in defending the United States, as well as their communities during the war. The book is also inspired by the ONI’s impact on the real-life Naval Criminal Investigation Service (NCIS), which was developed by ONI and previously named the Naval Investigation Service before it changed its name in 1992 to “emphasize the criminal mission of the agency,” Harmon told People.
“On the show we used to use the fact that no one knew who this agency was or what they did as a point of humor, but for those doing this difficult job for real, there was nothing funny about it,” Harmon said. “To provide these men and women a chance to tell their story, their REAL story, has been both fun and educational for me.”
Carroll Jr. also told People about the “seamless” experience of working with Harmon on Ghosts of Honolulu. “Through an 18 year relationship, Mark and I have developed a deep appreciation of what we can do together as a team,” he said. “Considering different options and approaches to storytelling is similar, whether it is a book or a television show.”
Carroll Jr., a former NCIS special agent, found several similarities to his previous career while writing the book. He also told People that he was especially impacted by Wada’s story. “He was using many of the same operational methods that I was trained in some 40 years later,” Carroll Jr. said. “I could definitely relate to the challenges he faced maneuvering in an environment where even his co-workers were not sure about what he really did.”
Harmon, for his part, told People that it felt “weird” to add author to his list of credits, which also include TV shows like The Love Boat, The West Wing and St. Elsewhere. “Actors tell stories, so that part is comfortable,” Harmon said. “[But] I have enjoyed great teachers and help, [and] the idea to grow and learn something new every day.”
What Carroll Jr. hopes readers get out of Ghosts of Honolulu was also disclosed to People. Carroll Jr. stated, “I want the book’s readers to be much more informed about the broad reach of our agency and the role it has played in our nation’s defense.” “Not just in terms of offering the Department of the Navy investigative support, but also in terms of the part it has played in maintaining national security.”
As for other upcoming projects, Harmon’s last credit listed is NCIS. However, The Hollywood Reporter did report in February 2023 that Harmon had signed with The Gersh Agency, a talent agency that has also represented actors like Brendan Fraser, Allison Janney, Patricia Arquette, Adam Driver and Mandy Moore.