premise: The Metal Men are a group of superheroes that appear in DC Comics. The characters first appeared in "Showcase" #37 and were created by writer Robert Kanigher and penciller Ross Andru. Debuting in the Silver Age of Comic Books, the characters have appeared in comic books and other "DC Comics"-related products such as animated television series, clothing, figurines and trading cards.
hypothesis: Ross Andru created the look of the Metal Men superheroes that appear in DC Comics. 
reason:  The characters first appeared in "Showcase" #37 and were created by writer Robert Kanigher and penciller Ross Andru. The penciller is the person draws the pictures and the writer creates the story so Andru is the one that created the heroes look for the comic. 