- Seymour Hicks
- Professor Heggie
- Nancy O'Neil
- Angela Heggie
- Gibson Gowland
- Angus
- Frederick Peisley
- Jimmy Andrews
- Eric Hales
- Jack Campbell
- Ben Field
- Piermaster
- Hubert Harben
- Prof. Blenkinsop Fothergill
- Rosamund John
- Maggie Fraser
- Robb Wilton
- Reporter
- Fewlass Llewellyn
- Scientist at Meeting
- Stafford Hilliard
- Macdonald
- John Jamieson
- McDougall
- Cyril McLaglen
- Mate
- John Miller
- Reporter in Pub
- Clive Morton
- Reporter / Photographer in Pub (uncredited)
- John Rae
- Villager in Pub
- Elma Reid
- Typist
- D.J. Williams
- Judge
