with writer-editor Robert Kanigher, Andru co-created the robot superheroes called The Metal Men in Showcase #37 (April 1962), going on to draw the first 29 issues of the lighthearted series Metal Men, from 1963 to 1968. Esposito said Kanigher "left the character design up to Ross and myself, under his supervision, of course."

Andru and Kanigher had several other notable collaborations.