Stephen Georg’s review published on Letterboxd :
Six years ago this month, I walked into my "Introduction to Film" class and sat down. It was the first film class I had ever taken at SCAD. The professor introduced himself and chatted with the class briefly, then he put a movie in for us to see. It wasn't like movies I had seen before. It was high-contrast, dark, confusing, artsy and weird. That film was Pi.
I remember thinking, "oh god, what have I gotten myself into..." But time passed, I watched other films, and now, re-watching it, Pi doesn't seem that weird. It's actually pretty good.
The film follows Max, a number theorist who believes that everything in nature can be understood with numbers. He's a genius, capable of doing huge number problems inside his head, but he also suffers from major headaches, extreme paranoia, and a myriad of other issues. Max sets his sights on the stock market, hoping to find a pattern and break the code. He does. Pretty soon a Wall Street firm is pounding at the door, interested in his work.
Max also meets a Hasidic Jew named Lenny, who is a fellow number theorist, but trying to crack the secrets of the Torah. Lenny informs him they're trying to find a very specific number—the same number Max stumbled upon when searching for a pattern in the stock market.
Okay, I lied, Pi is actually a little weird. The way I see it, if you don't like artsy films then you're going to hate this, and if you do like them, you've probably already seen Pi. It was the directorial debut of Darren Aronofsky, and in many ways the film feels like an early Requiem for a Dream. It certainly helps that the films share the same cinematographer (Matthew Libatique) and composer (Clint Mansell).
Overall, I liked the film, but honestly I'd recommend Requiem over Pi. They're not the same story but they feel very, very similar. There's some good stuff here but it's done even better in Aronofsky's second film. I feel like Pi is better suited as a history lesson once you see how fantastic Aronofsky's other works are.