Veteran TV, film and radio actor turned successful TV director and producer. Sweeney's entertainment career began in the waning days of the golden age of radio, first as an announcer and then as half of a popular comedy team. He moved on to the infant medium of TV where he made a niche for himself as a supporting player on several early sitcoms. Sweeney co-starred with Gale Gordon (later of "The Lucy Show") in a short-lived sitcom before landing what must have seemed like a plum role at the time: Fibber McGee on the NBC TV version of "Fibber McGee and Molly", the immensely popular radio sitcom. However the show failed and Sweeney shifted most of his attention to TV directing. As an actor, Sweeney is best known to film audiences as the smugly earnest undertaker in John Ford's "The Last Hurrah" (1958) and as Cousin Bob in Alfred Hitchcock's "Marnie" (1964).
Sweeney directed most of the episodes in the first three years of the long-running sitcom "The Andy Griffith Show". He next shifted generic gears as he went on to produce (with Bill Finnegan) the first six seasons of the immensely popular cop show, "Hawaii Five-O". Sweeney directed some episodes of that series as well as episodes of "That Girl", "Scarecrow and Mrs. King", "Matlock", and "Dynasty". He also helmed the popular "Andy Griffith Show" reunion TV movie, "Return to Mayberry" (1986).