Leonid "Lenya" Polivanov

Introduced as a Soviet space program official who begins a quiet, unofficial correspondence with NASA's Margo Madison, Lenya presents himself as cultured and reasonable, someone interested in the exchange of ideas across the Iron Curtain. He is careful, watchful, and impossible to read fully — a diplomat's charm layered over something more guarded.

Costa Ronin plays him with a stillness that makes every warm gesture feel calculated and every calculation feel almost sincere, so you're never sure which is which. The show uses him to dramatize the Cold War's paradox — genuine connection built entirely on mutual surveillance — and Ronin holds that contradiction without tipping his hand.