Pi (stylized as π)[a] is a 1998 American conceptual psychological thriller film written and directed by Darren Aronofsky (in his feature directorial debut).

[5][6] The story focuses on a mathematician with an obsession to find underlying complete order in the real world and contrasting two seemingly irreconcilable entities: the imperfect irrationality of humanity and the rigor and regularity of mathematics, specifically number theory.

Euclid malfunctions, printing out a seemingly random 216-digit number, as well as a single stock pick at one-tenth its current value, then crashes.

One of them, Marcy Dawson, offers him a classified computer chip called "Ming Mecca" in exchange for the results of his work.

As Max writes down the number, he realizes that he knows the pattern, undergoes an epiphany, and loses consciousness.

After passing out, Max goes to the bathroom where he stares at himself in the mirror before lighting a match and burning the piece of paper with the number.

Before production, to finance the complex visual sets and shots for the film, producer Eric Watson and director Darren Aronofsky asked every friend, relative, or acquaintance for donations of $100 each.

[3] To save money, various cost-cutting techniques were used, including using only the actors' clothes and thrift store purchases as costumes, and shooting all of the subway and outdoor city scenes illegally to get around paying expensive permits.

[3] For the main set, which was Max Cohen's apartment, Scott Vogel secured a section of his fathers's warehouse in Bushwick, Brooklyn.

A back room was cleared out and used as a sound stage,[11] where Max's Euclid computer was built and the majority of the film was shot.

During the climactic final scene, a pattern resembling a bifurcation diagram is apparent on Max's shattered mirror.

[14][c] Gullette and Margolis spent many hours learning the game at the Brooklyn Go Club and received help from Dan Weiner, one of three Go consultants credited to the film.

The numerological interpretation of the Torah and the 216-letter name of God, known as the Shem HaMephorash, are important concepts in traditional Jewish mysticism.

Another religious reference comes while Max is at the market looking for that day's newspaper, when a recitation citing Quran 2:140 can be heard in the background: "Or do you say that Abraham and Ishmael and Isaac and Jacob and the Descendants were Jews or Christians?

More than a decade after its theatrical release, the rights to the film reverted from Lionsgate (owner of Summit Entertainment and the Artisan library) back to Aronofsky, who sold it to A24 in 2023.

[17] Produced on a budget of $134,815,[3] the film was financially successful at the box office, grossing $3,221,152 in the United States[4] despite only a limited theatrical release.

The website's critical consensus reads: "Dramatically gripping and frighteningly smart, this Lynchian thriller does wonders with its unlikely subject and shoestring budget.

"[23] James Berardinelli gave the film three out of four stars, writing: "Pi transports us to a world that is like yet unlike our own, and, in its mysterious familiarity, is eerie, intense, and compelling.

Reality is a fragile commodity, but, because the script is well-written and the central character is strongly developed, it's not hard to suspend disbelief....It probably deserves 3.1416 stars, but since my scale doesn't support that, I'll round it off to three.