Desc: Trooper O'Brien: Directed by Jack Gavin. With Merle Ridgeway, Gordon Collingridge, Jack Gavin, Charles Stanford. Trooper O'Brien is a 1928 Australian silent film. It was a melodrama set during the "Ned Kelly era" about an orphaned girl raised by a policeman in the bush. It is one of the rare Australian films that still exist in its entirety.