Noonan grew up in the southern South Island, in Dunedin and Oamaru.After leaving school he began writing, notably drama such as The Rattle, whilst supplementing his income through work in radio and stage acting and as a regional television newsreader. He moved to Auckland in 1965, where he began writing for television. In 1969, he became the first script editor for the newly created television drama department of the NZBC. In this capacity he worked alongside and helped mentor a group of new writing talent including the likes of Roger Hall and Fiona Kidman. He left his editing position in the early 1970s, and in the proceeding years scripted several series