Thelma Grigg

Oddly named Hy Hazell stars as the title character, a music hall performer who, with partner and boyfriend (and co-star) Michael Medwin, blunders willfully into the criminal escapades of a trio of crooks. The boyfriend, the club owner, and Scotland Yard have all had their fill of her constant attempt to solve crimes, but this time she truly does. (imdb)

A famous director, Robert Grimble, comes to Australia to make a film about pioneering women and seeks for an unknown to play the lead role. He casts socialist Miss Hemingway, who soon proves to be temperamental. She is tricked into walking off the job by Jimmie Jones who wants his girlfriend Patsy cast. He succeeds and Patsy becomes a star