He did radio acting work with Hugh Denison's BSA Players (for Broadcasting Service Association, later to become Macquarie Players). He came to the attention of Australian Broadcasting Commission radio drama producer Lawrence H. Cecil, who was to act as his coach and mentor throughout 1939 and 1940. He was "Chris" in the Children's Session and the first Muddle-Headed Wombat.
Finch's next three films saw him support notable female stars: Sophia Loren in Judith (1966), Melina Mercouri in 10:30 P.M. Summer (1966) and Julie Christie in Far from the Madding Crowd (1967). He was reunited with Aldrich for The Legend of Lylah Clare (1968). The Red Tent (1970) was an expensive international adventure film, with Finch as Umberto Nobile.
George Finch was born in New South Wales, Australia, but was educated in Paris and Zürich. He was a research chemist when he moved to Britain in 1912 and later served during the First World War with the Royal Army Ordnance Depot and the Royal Field Artillery. In 1915, at Portsmouth, Hampshire, George married Alicia Fisher, the daughter of a Kent barrister. However, George Finch was not Peter Finch's biological father. He learned only in his mid-40s that his biological father was Wentworth Edward Dallas "Jock" Campbell, an Indian Army officer, whose adultery with Finch's mother was the cause of George and Alicia's divorce, when Peter was two years old. Alicia Finch married Jock Campbell in 1922.
George gained custody of Peter, who was taken from his biological mother and brought up by his adoptive paternal grandmother, Laura Finch (formerly Black) in Vaucresson, France. In 1925 Laura took Peter with her to Adyar, a theosophical community near Madras, India, for a number of months, and the young boy lived for a time in a Buddhist monastery. Undoubtedly, as a result of his childhood contact with Buddhism, Finch always claimed to be a Buddhist. He is reported to have said: "I think a man dying on a cross is a ghastly symbol for a religion. And I think a man sitting under a bo tree and becoming enlightened is a beautiful one."