James Gordon, Sr., owner of the Gordon syndicate, dispatches his roughneck son Jimmy to investigate why production has fallen off in his opal mine on an island off the coast of lower California. After an argument with his fiancée, socialite Lucy Andrews, Jimmy leaves for the island where he is met by Juan, McCool's servant who, along with Jasper Sneedham, has been cheating the company. On the launch, Juan tries to eliminate Jimmy by hitting him over the head, but the lad escapes and swims to shore where he is rescued by Sneedham's stepdaughter Nadine. Nadine takes Jimmy to the hut of mine foreman Fred Haimer, the only honest man on the island.
| Actor | Role |
|---|---|
 Jack MulhallJimmy Gordon | Jimmy Gordon |
 Ann ForrestLucy Andrews | Lucy Andrews |
 Donna DrewNadine | Nadine |
 Hayward MackSir Beverly Wyndham | Sir Beverly Wyndham |
 Alfred AllenJasper Sneedham | Jasper Sneedham |
 Ed BradyMcCool | McCool |
 Fred MontagueJames Gordon Sr. | James Gordon Sr. |
 Burton LawBeppo | Beppo |
| PPercy ChallengerFred Haimer | Fred Haimer |
 Harry MannBennie Zussbaum | Bennie Zussbaum |
| HHarry MorrisJuan | Juan |