Summary (tl;dr)

Mark Harmon is currently trending due to recent revelations from a podcast appearance about his career beginnings, and the release of his new non-fiction book, "Ghosts of Sicily," co-authored with Leon Carroll, Jr.

Essential Background

Mark Harmon is a renowned American actor, best known for his long-standing role as Special Agent Leroy Jethro Gibbs in the hit CBS crime drama NCIS, which he departed as a series regular in 2021 after 18 seasons. He continues to be involved with the franchise as an executive producer and narrator for the prequel series, NCIS: Origins. Beyond his acting career, Harmon has also ventured into writing, co-authoring historical non-fiction books.

The Full Story

Mark Harmon is generating buzz in April 2026 due to two primary reasons. Firstly, he recently appeared on "The Fifth Column" podcast, with a clip posted to YouTube on April 16, where he shared details about the pivotal, spontaneous phone call to producer Jack Webb that launched his acting career with an early role in Adam-12. This personal anecdote about his career origin has been widely reported by entertainment news outlets. Secondly, Harmon and co-author Leon Carroll, Jr. released their third book, "Ghosts of Sicily: The True Story of the Naval Intelligence Agents Who Courted the Mob to Fight Nazis in America and the Battlefields of Italy," on April 14, 2026. This new installment, following their successful "Ghosts of Honolulu" and "Ghosts of Panama," delves into a historical true story and is published by Harper Select.

Why It Matters

These keywords are trending because fans are interested in both new insights into Harmon's personal journey and his continued creative endeavors beyond his iconic NCIS role. The podcast appearance offers a rare glimpse into the early, formative years of his celebrated career, captivating those curious about his path to stardom. Simultaneously, the release of "Ghosts of Sicily" highlights Harmon's successful transition into authorship, providing his audience with new content and demonstrating his versatility and commitment to storytelling. This dual focus keeps him relevant and in the public eye, satisfying both long-time fans of his acting and those interested in his historical writing projects.

Geographic Location

• Virtual/Online (discussion of career origins on "The Fifth Column" podcast)
• Hollywood, Los Angeles, California, United States (location where Mark Harmon's early acting career began with Mark VII Limited)
• Nashville, Davidson County, Tennessee, United States (headquarters of Harper Select, publisher of "Ghosts of Sicily")