James Christopher Carmack (born December 22, 1980) is an American actor, singer, and former fashion model. He is known for his roles in three popular television shows—the teen drama series The O.C. (2003–2004) as Luke Ward, the country music drama Nashville as Will Lexington (2012–2018), and the medical drama Grey's Anatomy (2018–present) as Dr. Atticus Lincoln.
Carmack has also appeared in films, including The Butterfly Effect 3: Revelations, Into the Blue 2: The Reef, Love Wrecked, Beauty & the Briefcase and Alpha and Omega.