The plot follows a wealthy man (Roth) who attempts to abandon his family on vacation after the death of his mother.

Neil Bennett, a quiet man from London, is on vacation in Acapulco with his sister Alice and her two children, Colin and Alexa.

He ignores Alice's requests to come home and starts dating a friendly local named Berenice.

After Berenice falls asleep by his side, Neil abandons her and walks down the streets of Mexico City alone at night.

The film abruptly cuts from his sad face to the sounds of the beach's waves the following morning, the glaring sunshine, and the clothes and shoes Neil was wearing the previous night, left unattended on his chair with a beer nearby.

In July 2021, Tim Roth and Charlotte Gainsbourg were announced to star with Mexican filmmaker Michel Franco writing and directing.

The actor said a major aspect of the film was putting his undisturbed character in dangerous circumstances so "the audience has to make up their minds about what that says about him.

He also said he liked the film's original title, Driftwood, because it defined who his character was; a wandering, uncaring, and sometimes oblivious man impacting the people around him.

Iazua Larios, who plays Berenice, said the film was an exploration of people in different social classes "finding love and communicating in a strange way.

[15] The film was screened in six theaters in New York and Los Angeles in its opening weekend that included Q&A sessions with Franco.

[21] Outside the US and Canada, the film was released in Russia and the Commonwealth of Independent States ($80,069), Spain ($27,795), and Slovenia ($596).

The website's consensus reads: "Sundown's emotionally muted wavelength may be difficult for some viewers to tune into, but it's enlivened by Tim Roth's strong central performance.

"[22] Metacritic, which uses a weighted average, assigned the film a score of 70 out of 100, based on 27 critics, indicating "generally favorable" reviews.

[24][25][26][27][28] Xan Brooks of The Guardian gave the film five stars out of five, calling it "pitiless and pitch-perfect, an existential tour-de-force with shades of Albert Camus's The Outsider.

"[29] Writing for San Francisco Chronicle, Mick LaSalle said Sundown's greatest achievement "is harder to explain.