An electrical engineer, Stanley Stanfield (Onslow Stevens), brings his newest invention to the famous electrical wizard, Carl Van Dorn (James Durkins)--- a vest-like apparatus that enables the wearer to vanish, leaving only a shadow. Hey, back off...it's a good start.
Anyway, Van Dorn is vastly impressed and, with the aid of the machine, the pair set out to bring about the downfall of power-crazed Wade Barnett (Walter Miller) and his crony Dorgan (Dick Cramer), whose political-group activities, through a vicious smear campaign, had hounded Stanfield's father to death. Stanfield's efforts are complicated by the fact that his girlfriend, known to him as Gloria Grant (Ada Ince), is really Barnett's daughter, who has rejected her father and goes by an alias.
Wizard Van Dorn also stays busy inventing new gadgets to fight the gang with but, someway or another, he or Stanfield or Gloria always end up as the victim rather then Barnett, Dorgan or their henchies. Going back to the drawing board in chapter 10 (The Iron Death), Van Dorn comes up with a short-wave radio controlled robot and, in chapter 11 (The Juggernaut), he remotes it into a room to kill Barnett, but by mistake, the robot attacks Stanfield, who is tied helpless in a chair. Barnett was long gone.
They would have been better served by spending all their time and energy in trying to get rid of the shadow caused by the invisibility vest.
Toss in Ada Ince in the highest-budgeted film she ever made, and Edmund Cobb as a derby-hat wearing henchie (looking a lot like "Doiby" Dickles, the Green Lantern's cab-driving pal) and add Kenneth Strickfaden's art-deco lab and amazing electrical gadgets...and this becomes a Keeper.