Richard Treat Williams (born December 1, 1951) is a Screen Actors Guild Award–nominated American actor and children's book author who has appeared on film, stage and television. He first became well known for his starring role in the 1979 film Hair. From 2002 to 2006, he was the star of the television series Everwood. He is also known for starring in "The Substitute" franchise, beginning with the 2nd movie of the series The Substitute 2.
Williams was born in Rowayton, Connecticut, the son of Marian (née Andrew), an antiques dealer, and Richard Norman Williams, a corporate executive. His maternal great-great-grandfather was Senator William Henry Barnum of Connecticut, the third cousin of the showman P. T. Barnum, and a distant relative was Robert Treat Paine, a signer of the Declaration of Independence. Williams graduated from the Kent School in Connecticut and Franklin and Marshall College. During his adolescence, Treat was often affectionately referred to by nicknames such as "Sweet Treat" and "Big Meat Treat". These later resurfaced when Williams was featured in the February 1980 edition of Playgirl.
Williams made his film debut in the 1976 thriller film Deadly Hero. He came to world attention in 1979, when he starred in the Miloš Forman film Hair, which was based on the 1967 Broadway musical. He has gone on to appear in over 75 films and several television series, including, most notably, 1941 (1979), Once Upon A Time In America (1984), Dead Heat (1988), Things to Do in Denver When You're Dead (1995), and Deep Rising (1998).
Williams lives with his wife, Pam Van Sant, and two children, Gill and Ellie, in Manchester, Vermont. The family also has a home in New York City.