Following with "The Masked Marvel": one of the interesting things about it is that it deals with the theme of a double life, something which Laughton could have portrayed well.
Laughton was always keen on giving a character a well-rounded, multi-layered self. Never an actor to conform himself with a flat, one dimensional delivery, he had successfully embodied respectable citizens with a skeleton in the closet, such as in "Payment Deferred" or "The Suspect". Those cases, though, deal more with people concerned with the cover-up of an accidental -or temporary- disruption (i.e. crime) in their routinely lifestyle than a fully fledged double life. "The Masked Marvel", in that sense, would have given him the chance of playing a man living a double life in a sustained way (Not that he would have had to gone too far to source himself, ha).
In this context I think that it would be appropiate to quote A.E. Wilson's (1) very perceptive description of Laughton's villains: "Charles Laughton very often hands out a neat line in villainy of the subtle hand. He is not the bold and desperate villain who could as soon drown, poison or tie to the railway lines or mill-wheel the discarded victim of his cruel deceit as he would smoke or crush a cigarette. He is of the furtive and secret kind who would blush to let his bad deeds be known and who really has no stomach and relish for wickedness (2). This is not bold, black villainy as the good old Adelphi knew it; it is rather a wishy-washy sort of grey according to the old standards."
"(...) furtive and secret kind"... One wonders whether Mr. Wilson had an X-ray eyesight, or maybe Laughton did want to tell, in an oblique way, but tell, after all?
(1) From the book "Theatre Guyed. The Baedeker of Thespia" (1935) by A.E. Wilson. Introduction by Sidney Horler. Illustrations by Tom Titt. Published by Methuen (2) Not that it was always that way: Laughton played well bold, black villainy in "A Man With Red Hair" or "White Woman" .
Dwelling in an arriki-town beside Barcelona.
Obviously interested in Charles Laughton! Yet it is true that there are more things in life: tiger-nut milk, Hideko Takamine or downhill races on ball-bearing wheel carts, just to name three items...