Peter Williams (born December 31, 1957) is a Jamaican-born Canadian actor. He is known for playing Apophis, a primary antagonist on Stargate SG-1. The majority of his work has been in television, including his role as the primary villain Apophis in the first four seasons of Stargate SG-1 (plus a few appearances thereafter).
However, he has also appeared on the big screen in films such as Catwoman and The Chronicles of Riddick. His brother Stephen is also in the entertainment business, and has directed several episodes of television shows including Dark Angel, Crossing Jordan, and Lost.
In 1995, two years prior to Stargate SG-1's premiere, Williams starred in the 1995 movie Jungleground with three other actors from the Stargate franchise: Torri Higginson (Elizabeth Weir), J. R. Bourne (Martouf), and Lexa Doig (Dr. Lam). In 2007, he played the lead, Gene Wright, in Frances-Anne Solomon's feature film A Winter Tale.