A young forestry graduate, Jim Thornton, is involved in a race between timber companies to fill a major contract. Jim has joined the crew of a genial timber baron, Burbridge, and foils attempts by a rival, Blake, to sabotage their work. J. Alan Kenyon's special effects are the highlights of the film with comic relief provided by Joe Valli as a Scottish timber-train driver amorously pursued by a shrill-voiced maid of the Burbridge's country house.

Joan (Helen Twelvetrees) is a Canadian, adopted by Ma Dawson (Nellie Ferguson), a struggling horse breeder and trainer. Joan thinks "legs don't make a race horse, it's blood", and so she buys an unwanted thoroughbred colt called Stormalong. Helped by Ma's son Tommy Dawson (Frank Leighton), Joan restores the horse to health and fitness, and soon enough the horse is winning race after race, becoming a favourite for the Melbourne Cup.

Bluey and Darkie are first world war veterans who save an ailing racehorse from destruction.

The story concerns an attempt by fifth columnists to gain control of Australia's supplies of wolfram, a mineral used in the manufacture of munitions, involving a new wolfram field owned by Francis Jamieson (Marshall Crosby).