St. Elsewhere actor who gained widespread recognition as Leroy Jethro Gibbs in the hit CBS series NCIS. His film credits include Wyatt Earp, Fear and Loathing in Las Vegas, Freaky Friday and Weather Girl.
He graduated cum laude from UCLA with a degree in communications. He also played football at UCLA before going to Hollywood to star on the TV Series NCIS.
In 1977, he was nominated for a Primetime Emmy Award for Outstanding Supporting Actor for his role in Eleanor and Franklin: The White House Years.
He is the son of football star Tom Harmon. He married Pam Dawber in March 1987.
His sister's mother-in-law was Harriet Nelson from The Adventures of Ozzie and Harriet.