From the Z-Man games web site and the back of the main rulebook:
In the far future, rich eccentric Clayton Douglas creates a distant planetary colony using elements of technology and architecture from 1920s through 1940s America. Decades of increasingly corrupt and ineffectual Mayors follow Douglas' death, eventually culminating in the administration of the tyrannical Mayor Hoodler. Hoodler creates an oppressive police state designed to ruthlessly control society, forcing total conformity to Douglas' original vision. The characters exist in this dystopia amidst cybernetic detectives, mutant mobsters, alien-touched drug lords, vat-bred blue-collar workers, and human hybrids that can see into an alternate dimension known only as the Jade.