In 1938, a team of German agents kidnaps Professor Ellwood Henderson to steal his Orotron machine, which can extract gold from seawater. Led by the mysterious "The Master Key", the agents pose as a private investigator and are trailed by federal agent Tom Brant, police detective Lieutenant Jack Ryan, and newspaper reporter Janet Lowe. With the help of Police Chief William J. O'Brien and his secretary Dorothy Arnold, Brant and Ryan work to uncover the identity of "The Master Key", who seems to have insider knowledge. Along the way, a group of boys, led by candy store owner Aggie and her club leader Migsy, aid in the quest. The serial features stock street footage from earlier Universal films.
The Master Key
Ruthless Nazis pursue a machine capable of converting seawater into gold, prompting a team of government agents to take extreme measures to thwart their plans.
