Shaun Paul Cassidy (born September 27, 1958) is an American television scriptwriter and producer.A retired actor and singer, he is known for starring in the television series The Hardy Boys Mysteries (1977–1979) and Breaking Away (1980–1981), as well as having several hit records in the 1970s.In the 1980s, he had a three-month stint on the daytime soap General Hospital and acted on Broadway and in the West End of London. Since the mid-1990s, Cassidy has worked exclusively as a writer and producer in television, creating a number of television series, including American Gothic, Roar and Invasion. He is the eldest son of Shirley Jones and Jack Cassidy.His older half-brother was David Cassidy.