This episode introduces the Classic Tetris World Championship (CTWC), which began in 2010. First we recount the history of the tournament leading up to 2014, its fifth year. Then we meet some of the key players we'll follow. We see qualifying for the tournament, fill in (most of) the bracket, and show our first match. At the end, we meet the five key players we'll follow for the rest of the series.

We learn how players have trained for the tournament. Some have extreme training regimens...and some haven't played in a year. We meet Trey Harrison, who has programmed a Tetris simulator to help him train for the tournament. We also learn about his history with Tetris legends Thor Aackerlund and Jonas Neubauer. Finally, we learn the unusual way Trey earned his spot in the bracket...and what happens as a result.

We start by exploring how Tetris experts think about the game. Then we learn about how, in the small Classic Tetris scene, close friends often compete and feel bad about it—each person wants to win, but nobody wants their friend to lose. Finally, two friends do battle, in an intense match dubbed "the buzzer beater" by commentator James Chen.

We learn how the environment of the tournament—its noise, lights, cameras, and chaos—affects players. Jonas Neubauer explains how he embraces that aspect of the competition, while competitor Terry Purcell works to block it out and concentrate on the game. We learn why the CTWC uses old CRT TVs for the competition. And finally, we learn how a player's nerves factor into competition. This match is very heavy on gameplay, with four key matches mixed in with the scenes listed above. By the end, we have set up the final match.

Writing a full description of this episode would spoil the show, so we're going to be vague here. Two players ended up on top in Episode 4. We review their competitive history and what's at stake for each of them. Then we see the episode best-of-five final match. After that, the winner is interviewed extensively. At the end, we learn what happened to our key players since the 2014 tournament, and reflect on what it means to be part of a community.