Under the Big Top – touring show with George Sorlie, various Queensland towns, 1936, playing Herbert Hughes in Laughter of Fools by H.F. Maltby, Smithers in Married by Proxy by Avery Hopwood, Peter in Fair and Warmer by Avery Hopwood, Hunter in Ten Minute Alibi by William Armstrong – all directed by William McGowan with Murray Matheson, Rosalind Kennerdale, Leslie Crane, Eva Moss, Norman French, Julia Adair and George Douglas.
During his war service Finch was given leave to act in radio, theatre and film. He appeared in a number of propaganda shorts, including Another Threshold (1942), These Stars Are Mine (1943), While There is Still Time (1943) and South West Pacific (1943), the latter for Ken G. Hall. He also appeared in two of the few Australian feature films made during the war, The Rats of Tobruk (1944) and the less distinguished Red Sky at Morning (1944).
Finch was married three times. In 1943, he married Romanian-born French ballerina Tamara Tchinarova; they worked together on a number of films. They had a daughter, Anita, born in 1950. They divorced in 1959, after she discovered his affair with actress Vivien Leigh in California. He then married South African-born actress Yolande Turner (née Yolande Eileen Turnbull); they had two children together, Samantha and Charles Peter. During their marriage, Finch had an affair with the singer Shirley Bassey. Bassey had a daughter, also named Samantha, born in 1963; Bassey's husband at the time, the openly gay film producer Kenneth Hume, believed that Finch was her biological father. Finch and Turner divorced in 1965. In 1972 Finch married Mavis "Eletha" Barrett, who was known as Eletha Finch. They had a daughter together, Diana.