Taken from the Paramount release book, 1927.
"The most amazing and ultra-modern picture ever made. A drama of New York a hundred years from now, produced on a stupendous scale by the makers of Variety, with all the realism that made Variety popular and, in addition, effects that stagger the imagination. Audiences will talk about it for years to come."
What, no robot? That's like trying to promote Jaws and leaving out the shark. No wonder Metropolis was a flop in North America.