- Clyde Beatty
- Self
- Cecilia Parker
- Ruth Robinson
- Syd Saylor
- Larry Henderson
- Warner Richmond
- Sharkey
- Edward LeSaint
- Capt. Robinson
- Wheeler Oakman
- Kirby (Mary R Mate)
- Lew Meehan
- Flynn (Mary R Crewman)
- Max Wagner
- Slade (Mary R Crewman)
- Wes Warner
- Jackman (Mary R Crewman)
- Harry Holman
- Maitland
- Crauford Kent
- Prof. Livingston
- The Hagenbeck-Wallace Animals
- Circus / Jungle Animals (archive footage)
- Ernie Adams
- Assistant Animal Handler
- Jack Carlyle
- Mary R's Cook
- Jim Corey
- Steve
- George 'Gabby' Hayes
- Doctor
- Lloyd Ingraham
- Dirigible Captain
- Mickey Rooney
- Boy with Dog
- Hal Taliaferro
- Sandy
- Slim Whitaker
- Slim
- Lloyd Whitlock
- Howard
- Charles Williams
- Cub Reporter
- Maston Williams
- Thompson
