One month after the events of the first season, Citadel spies are underground and being hunted by Manticore agents around the world. They're pulled out of hiding to join forces with a new team of unconventional spies when Manticore's Brazilian billionaire Paulo Braga threatens to unleash a cataclysmic piece of technology, built by Citadel's own Bernard Orlick, into the world.

本剧为太空竞赛题材剧《为全人类》的衍生剧，是同一设定下的全新篇章。
《星城》将我们带回太空竞赛另类历史重述的关键时刻——苏联成为首个实现载人登月的国家。但这次，我们将从铁幕后方探索这个故事，展现苏联航天计划中宇航员、工程师以及潜伏其中的情报人员的生存图景，以及他们为推动人类进步所承担的风险。