Government agents battle a gang of Nazis who are trying to use the Orotron machine, which can turn seawater into gold.


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Complete credited cast:
Agent Tom Brant
Herman, Chief Thug
Migsy (Street Urchin) (as Alfred La Rue)
Jerry Shane ...
Dan, Boys' Club Member
Neyle Morrow ...
Spike, Boys' Club Member (as Neyle Marx)
John Eldredge ...


Universal's 64th of 69 sound-era serials (between "Jungle Queen" with Ruth Roman and their 2nd version of "Secret Agent X-9" with Lloyd Bridges), is set in 1938 with Nazi agents kidnapping scientist Professor Ellwood Henderson in order to get his Orotron machine that can extract gold from seawater. Operating under the secret leadership of "The Master Key", with the operatives headed by a German agent posing as a private investigator named Garrett Donovan, the gang is trailed by Federal agent Tom Brant, aided by police detective Lieutenant Jack Ryan and newspaper reporter Janet Lowe. Also aiding in the quest is Police Chief William J. O'Brien and his secretary Dorothy Arnold. It takes Brant nearly 12 of the 13 episodes to figure out that since the Nazis learn of his and Ryan's plans almost before they clear police headquarters, then "The Master Key" must be somebody close to them. Most of the leg-work is done by a group of boys under the leadership of candy-notions store owner Aggie ... Written by Les Adams <>

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Release Date:

24 April 1945 (USA)  »

Also Known As:

A Chave Mestra  »

Company Credits

Production Co:

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Technical Specs


(13 episodes)

Sound Mix:

(Western Electric Recording)

Aspect Ratio:

1.37 : 1
See  »

Did You Know?


Chapters: 1) Trapped by Flames, 2) Death Turns the Wheel, 3) Ticket to Disaster, 4) Drawbridge Danger, 5) Runaway Car, 6) Shot Down, 7) Death on the Dial, 8) Bullet Serenade, 9) On Stage for Murder, 10) Fatal Masquerade, 11) Crash Curve, 12) Lightning Underground, 13) The Last Key. See more »


At the beginning of each chapter, we are told the story is taking place in 1938, but 1939, 1940 and 1941 model automobiles are frequently seen and even used by the principal players on various occasions. See more »


Title Card: This is just a story. Like many good stories, it never happened and never could happen... but let us imagine that it is 1938, somewhere in the United States.
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Edited from Gang Busters (1942) See more »

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User Reviews

M-764 Reporting
5 September 2004 | by (Flushing, NY) – See all my reviews

Elwood Henderson invents the Orotron, a large device which can extract various minerals and elements in their minute quantities from sea water. Nazi agents (the serial, released in 1945, is set in 1938) plan to use the Orotron in order to obtain enough gold to buy up key American industries for their own use and purpose. Henderson is also taken prisoner by the Nazis, since he has to manufacture the gas tubes in order to make the Orotron work, when the present ones wear out. Government agent Tom Brant, police detective Jack Ryan, and reporter Janet Lowe, team up to find Henderson and round up the agents responsible for his and the Orotron's disappearance, including the Master Key, the unknown head agent of the Nazis in the US. Very good script overcome some of the weak fights in the serial. Many of the cliffhangers are so-so, and at times just look like the writers put them in there from making the chapters run a reel extra. Stone, Moore, & Wiley are all believable as Brant, Ryan, and Lowe respectively. Addison is very villainous Donohue, second Nazi in command. LaRue is as good as he every would be as the leader of Lowe's teenage reporter friends, but Fougler has one of his better roles as Henderson. Great ending to the serial, one of the few that respects the intelligence of the viewer. Rating, based on serials, 8.

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