Watson was born in Alexandria, Louisiana. He attended Louisiana Tech on a music stipend for two years before transferring to Berea College in Berea, Kentucky, where he performed for the first time on stage as Petruchio in a production of Shakespeare's The Taming of the Shrew. During and after his years at Berea, he worked in outdoor dramas, dinner theaters, and small repertory groups.
In 1989, with a new commitment to film, Watson began pursuing feature film roles. By 2005, he had appeared in 43 feature films such as Sommersby, Something To Talk About, Assassins, Rosewood, I Know What You Did Last Summer, From Dusk Till Dawn 2, I Still Know What You Did Last Summer, Austin Powers: The Spy Who Shagged Me, and Songcatcher. As of 2005, seven of the films he has appeared in, combined, have grossed over $850 million.
His television credits include eight made-for-television movies including Blind Vengeance and Justice in a Small Town; and seven television series, American Gothic, The Young Indiana Jones Chronicles, Matlock, Lazarus Man, JAG, Walker, Texas Ranger, and Prison Break.
Watson also gave a performance with Jennifer Love Hewitt as a special guest on Saturday Night Live and more recently, on Ghost Whisperer, episode 218 "Delia's First Ghost". Since 2005, he has appeared as a recurring cast member on NCIS.