Atomic Heart looks like it's set in a post-apocalypse, but it isn't. Instead, it's an ARPG set in an alternate timeline that explores what could have happened in the USSR following World War 2.
Set in 1955, there are plenty of surprising technological advancements, all centered on communism and aggression towards the Western world. You play as a KGB officer who finds himself in the middle of a huge robotic malfunction at "The Facility." Inside, you'll be faced with hostile machines that were originally made to be used in wartime combat.
So much of the game is still shrouded in mystery, and it's been rumored that the game has undergone significant changes since it was first announced in 2018.