Roy Thinnes (born April 6, 1938) is an American television and film actor best known for his portrayal of lonely hero David Vincent in the ABC 1967–68 television series The Invaders. He starred in the 1969 British science fiction film Journey to the Far Side of the Sun (also known as Doppelgänger), and also played Manhattan District Attorney Alfred Wentworth in the pilot episode of Law & Order.