American actor Brian Dietzen is renowned for his long-running role on the military procedural drama "NCIS" (CBS, 2003- ). A native of the Midwest, he got his start in theater productions and won his first screen roles while in his mid-twenties. After appearing on the short-lived comedy show "My Guide to Becoming a Rock Star" (The WB, 2002), Dietzen made his feature debut in the universally panned "American Idol" spin-off "From Justin to Kelly" (2003). These career setbacks swiftly receded, however, when he was cast in 2004 in the recurring part of nerdy technician Jimmy Palmer on "NCIS." While Dietzen occasionally moonlights in low-budget films, "NCIS" has remained his main focus, let him develop his slightly awkward character over numerous seasons on the consistently popular series.
Born in suburban Illinois, Dietzen studied drama in the acting program at the University of Colorado at Boulder and gained stage experience before auditioning for television parts. In 2002, he joined the cast of the sitcom "My Guide to Becoming a Rock Star" as Owen, drummer of the show's fictional band, but the plug was quickly pulled. While appearing in the feature musical "From Justin to Kelly" likely seemed like a good opportunity at the time, the critical backlash against the movie was fierce, and Dietzen had to soldier on. His persistence soon paid off, however, since he landed a recurring gig on "NCIS." Cast as Jimmy Palmer, the bookish assistant to medical examiner Donald "Ducky" Mallard (David McCallum), Dietzen gradually became more of a presence on the naval crime drama. With the weekly series keeping him busy, he worked on other productions from time to time, including "Congratulations" (2012), an indie film that he co-wrote and starred in, and a guest spot on the mystery series "Perception" (TNT, 2012-14). In 2012, with more than 100 "NCIS" episodes under his belt, he was promoted to a series regular.