John Dobbie

After being fired from his job at a grocer, George, gets a job as a stableboy at a local stud farm run by the Fleming family. He befriends the horse Hotspur who is a favourite to win the Melbourne Cup, and develops a strong whistle which is used to make the horse run fast.

George is a disaster-prone zoo attendant who accidentally discovers a substance that accelerates motion, enabling his greyhound to run faster. This attracts the interest of a gang of criminals, who kidnap George's dog and plan to substitute their own in an important dog race. George and his friends defeat the crooks and their dog wins the race.

After her father's death, socialite Elaine Fleetwood promises to marry a man she does not love. However, she leaves him at the altar during a wedding ceremony, cuts her hair and decides to disguise herself as a boy and go prospecting in northwest Tasmania. She meets a handsome miner who figures out she is a woman, saves her from a villain and marries her.