After graduating from the
AFI Conservatory, Aster wrote and directed several more short films between 2011 and 2018, often teaming with his AFI Conservatory friends Alejandro de Leon and
Pawel Pogorzelski. The most notable project was the short
psychological horror film
The Strange Thing About the Johnsons (2011), which follows the members of a suburban family in which the father finds himself trapped in an
incestuous relationship with his abusive son. The film was Aster's
thesis film while studying at the AFI Conservatory, and was later screened at film festivals; it premiered at the
Slamdance Film Festival in Utah on January 22 before leaking online in November, where it went
viral. Film website Short of the Week wrote that the comments on the film's
YouTube page had "everything from effusive acclaim to disgusted vitriol [...] in terms of the internet, that means it's a hit". Aster worked on the film with fellow AFI students. He first conceived the story while discussing taboos with his friends, including the film's star Brandon Greenhouse, before starting his first year at AFI. and was theatrically released in the United States on June 8. It was acclaimed by critics, with
Toni Collette's performance receiving particular praise, and was a commercial success; it grossed over $80 million on a $10 million budget, becoming
A24's highest-grossing film worldwide.
Peter Travers of
Rolling Stone named it the scariest film of 2018. Aster next wrote and directed the
folk horror film
Midsommar (2019), which was also produced by A24. It follows a group of American university students who travel to Sweden for a festival that occurs once every 90 years and find themselves in the clutches of a cult claiming to practise
paganism.
Midsommar was theatrically released in the United States on July 3. The film received positive reviews from critics, with many praising Aster's direction and
Florence Pugh's performance. Aster's original 171-minute cut of the film, which A24 asked him to trim down for a wide theatrical release, had its world premiere at the
Film Society of Lincoln Center in New York City as part of its Scary Movies XII lineup on August 20. For his work on the film, Aster received a nomination for
Best Screenplay at the
29th Gotham Independent Film Awards. In June 2019, Aster and Danish producer
Lars Knudsen announced that they had launched a new production company called Square Peg. In June 2020, Aster said his next film would be a "nightmare comedy" that lasts for four hours. In February 2021, A24 announced that Aster would write and direct
Beau Is Afraid (2023) as its third partnership with him. The film follows an anxiety-fueled and paranoid middle-aged man who must venture out on a surreal odyssey to visit his mother's home. It was originally titled
Disappointment Blvd. It was released in theaters on April 21. It ultimately lost the studio over $35 million. Speaking about the film's critical and commercial shortcomings, Aster said in 2025: "I was pretty sad that it was so maligned […] it was a bummer. It lost money. Critically, I wouldn’t say it was reviled, there’s just no consensus whatsoever... There are things that I would do differently if I did it now... I think I ejected a number of people from the theater with that [last hour]." In 2021, Aster signed a first-look TV deal with A24. In August 2022, it was announced that Aster would reteam with A24 to produce
Kristoffer Borgli's third feature film
Dream Scenario, with
Nicolas Cage attached to star. The film would be produced by Square Peg, which also expanded its slate to include films by
Kantemir Balagov,
Guy Maddin,
Don Hertzfeldt, and
Sebastián Silva, as well as television adaptations of
J. G. Ballard's
The Drowned World,
Nick Drnaso's
Acting Class, and
Junji Ito's
Uzumaki. Aster wrote and directed the
neo-Western political satire film
Eddington (2025), which was co-produced by A24 and Square Peg. Set in 2020 during the
COVID-19 pandemic and
George Floyd protests, the film examines the political and social turmoil in the fictional town of Eddington,
New Mexico caused by the contested mayoral election fought between the county sheriff and the town's mayor. The film debuted on May 16, 2025, in competition at the
Cannes Film Festival. It was released in theaters on July 18. It received mixed reviews from critics, who praised its ambition but found its satirical elements lacking. ==Upcoming and unfinished projects==