David Ian Hewlett (born April 18th, 1968) is an English-Canadian actor, writer, director, and voice actor best known for his roles as Dr. Meredith Rodney McKay on the Canadian-American science fiction TV shows Stargate SG-1, Stargate Atlantis and Stargate Universe, as David Worth in the 1997 Canadian psychological horror film Cube, as Grant Jansky on the 1996 Canadian TV series Traders, and as Douglas Hunsiker in Rise of the Planet of the Apes.
In addition, Hewlett is also known for his role in the 1988 horror movie, Pin (film) or "Pin: A Plastic Nightmare" as well as the 1991 science-fiction movie, Scanners II: The New Order.