I thought it was gonna be about the guy who actually made Tetris, but no they cover that in 2 minutes at the beginning and the rest of the movie is about the American copyright lawyer trying to get the rights for Nintendo.
It's literally all about how bad the USSR is and how good corporations like Nintendo are. When the American arrives in Moscow they take his passport down to an evil KGB bunker and the whole movie shifts to being tinted blue and grey.
There's literally a scene where the Russian programmer says to the American "we want to be free, we want your coca cola and Levi's jeans". If it wasn't so boring this would read as satire of American media in the Cold War.
There's a hilarious comedy about all scientific research in Moscow coming to a screeching halt as Tetris spreads through the city's research computer labs like a wildfire but the world isn't ready for that.