Hughes was memorable in several notable films of the late 60s and early 70s, including "Midnight Cowboy" (1969) as an aging gay john who gets beaten by Jon Voight; as a war-loving general in "Where's Poppa" (1970); and as an apparently lost patient in "The Hospital" (1971). As his features grew more grizzled and his voice endearingly gruff, Hughes came to specialize at playing cantankerous and/or eccentric oldsters (e.g. the vampire-hunting grandfather in "The Lost Boys" 1987; the grandfather of NBC-TV's "Blossom" in its first two seasons). His most celebrated role both on Broadway and in film was "Da" (staged in 1978 and filmed ten years later), an irascible Irish father who visits his son after his death. Hughes won the Tony for best actor for his stage performance.
Hughes became a TV fixture in the 70s with guest shots, superior TV-movies and specials ("Pueblo" 1973 and "The UFO Incident" 1975), and recurring roles on popular sitcoms. He was the often exasperated but always witty Father John Majesky on "All in the Family" and the moody father of Dr. Bob Hartley on "The Bob Newhart Show". Hughes also starred in several enjoyable if short-lived sitcoms, "Doc" (CBS, 1975, 1976), "Mr. Merlin" (CBS, 1981-82), and "The Cavanaughs" (CBS, 1987-89). He memorably pulled out all the stops to play a low down evil landlord who receives a hellish comeuppance in "Trick or Treat" (1983), a syndicated special that served as the pilot for "Tales From the Darkside". Hughes' feature credits in the 90s include the comedies "Doc Hollywood" (1991) and "Sister Act 2: Back in the Habit" (1993).