Synopsis by Hal Erickson
The biggest surprise in The Hidden Spring was that leading man Harold Lockwood appeared without his perennial leading lady May Allison. Lockwood stars as Donald Keeth, a young lawyer who sets up shop in the copper-mining town ruled by wealthy Quartus Hembley (Herbert Standing). Whenever anyone has stood up to the despotic Hembley in the past, that person has "disappeared" with the assistance of the copper king's brutish henchman Olaf Erickson (Arthur Milette). Thus, when Keeth crosses swords with Hembley, the local miners grit their teeth and await the inevitable. But neither Hembley nor Erickson have reckoned with the resourcefulness of Keeth, nor with the intense loyalty of Keeth's faithful -- and ferocious -- pet dog Mirabeau (played "by himself").