Manhunt Of Mystery Island - 1945 - 6/10

Republic serial.
The villain kidnaps two scientists to build him a device to control unlimited planetary energy through radium.
Lance, the lunkheaded hero, could take a punch; he got a pounding every episode.
Luckily Linda Stirling was in the cast to bail him out, or shoot a handful of baddies d-e-a-d.
Fights were better than most because the chief henchman was Kenne Duncan, who was a specialist in leaping, flying though the air fisticuffs.
The head baddie goes by Captain Mephisto, and he has a magic, electrical chair (fan behind that sprays sparks).
With the chair he can transform his features into anyone he chooses.
Does he pick President, movie star, four star general?
Nooo! He opts for the pirate look: tattoo, cutlass, big hat, face scars.