Muse Watson Gravel (born Robert Gravel; July 20, 1948), commonly known as Muse Watson, is an American actor notable for his recurring roles of Mike Franks on NCIS and Charles Westmoreland / D.B. Cooper in Prison Break, and film roles as Hank Corrigan in Something to Talk About, and Ben Willis, the killer in I Know What You Did Last Summer and I Still Know What You Did Last Summer.