According to the "Robert Downey Jr Film Guide" website, Marek Kanievska suggested Robert Downey Jr. and Andrew McCarthy should go out and party to 'get into character' which ended with Downey in the middle of Santa Monica Boulevard, howling at the moon, and McCarthy had to bail him out of jail.

Because the novel didn't have a central plot or a core set of protagonists, but was more a set of interwoven events happening to a larger group of friends, this film differs considerably from the novel. In a surreal twist, the sequel novel, 'Imperial Bedrooms', has the original novel's characters aware of the film version of "Less Than Zero".

Robert Downey Jr. plays a drug addict in the film. This proved prophetic, as he suffered drug and alcohol addiction in later life. He recalled: "Until that movie, I took my drugs after work and on the weekends. That changed on Less Than Zero (1987), the role was like the ghost of Christmas future. The character was an exaggeration of myself. Then things changed and, in some ways, I became an exaggeration of the character".

Brad Pitt was paid US $38 for his uncredited cameo appearance.

Bret Easton Ellis hated the film initially. He admits that the film bears no resemblance to his novel but that it captured "a certain youth culture during that decade that no other movie caught", and felt that it was miscast with the exceptions of Robert Downey Jr. and James Spader. Furthermore, he has said, "I think that movie is gorgeous, and the performances that I thought were shaky seem much better now. Like, Jami Gertz seems much better to me now than she did 20 years ago. It's something I can watch".

First film where Robert Downey Jr. was billed as "Robert Downey Jr." whereas all previous productions Downey had been billed simply as "Robert Downey".

A test screening of 15 to 24 year olds revealed that the sample disliked Robert Downey Jr.'s character. So reshoots were conducted with additional footage to show his and Jami Gertz's characters in a better light which included the happy and celebratory early graduation sequence.

Cinematographer Edward Lachman has said that the completed picture was originally a lot edgier and the 20th Century Fox studio, who felt the property was too edgy anyway and had limited the film's cost budget, wanted to tone down the movie and make it more commercial audience friendly, and did this by taking the film away from director Marek Kanievska in post-production.

Despite the rough experience of the shoot, Robert Downey Jr. considers this movie to be one of his all time favorite movies of his own, citing his performance of Julian Wells as "the ghost of Christmas Future", to his personal life.

The film was made and released about two years after its source novel of the same name by Bret Easton Ellis had been first published in 1985.

Keanu Reeves was originally to play the character Clay Easton. Eventually, the role was cast with Andrew McCarthy.

Both the book and film of Less Than Zero (1987) and its reported sequel, titled Imperial Bedrooms, are named from an Elvis Costello song and album respectively. "Less Than Zero" is the first single off the album "My Aim is True" (1977) whilst "Imperial Bedroom" is the name of Costello's 1982 album.

Cinematographer Edward Lachman remembers that originally the film was a lot "edgier" and that the studio took it away from Marek Kanievska. He also recalled a scene he shot with Red Hot Chili Peppers: "The Red Hot Chili Peppers were in that film and the studio became very conservative and they said, 'Oh the band, they're sweaty and they don't have their shirts on.' They destroyed an incredible Steadicam shot, all because they had to cut around them being bare-chested."

Unlike the movie, in the novel Clay Easton is identified as bisexual.

James Spader was briefly considered to play Clay Easton before the producers felt he would be more effective and stronger as the character Rip.

Third of three movies featuring James Spader and Andrew McCarthy. The first movie was Pretty in Pink (1986) and the second movie was Mannequin (1987). All three titles were first released during 1986-1987.

The party sequence with all the television screens was filmed at a real 1980s Hollywood nightclub in Los Angeles.

Second of three movies featuring James Spader and Robert Downey Jr.. The first movie was Tuff Turf (1985) and the third movie is Avengers: Age of Ultron (2015).

In an interview, source novelist Bret Easton Ellis once said of this film adaptation of his book 'Less Than Zero': "Of course, I envisioned everybody in the book as blonde and everybody in the movie is a brunette".

Stephen Colbert auditioned for a role in this movie.

Jami Gertz is the actress who plays Blair in this movie based on the first novel by Bret Easton Ellis. In another book written by Ellis, "American Psycho", Patrick Bateman inquires about actress Jami Gertz at the Video Visions video store in New York's Upper West Side. The video store clerk does not know who Gertz is. Bateman then fantasizes briefly about having sex with Gertz while trying not to pay attention to someone talking to him.

The last name of Andrew McCarthy's character, Clay Easton, is the same name as the middle name of source novelist Bret Easton Ellis. Clay's surname was not given in Ellis' source novel "Less than Zero". Its use here in this movie is a direct reference to the author.

According to the 1987 article "Sanitizing a Novel for the Screen" published in 'The New York Times', Pulitzer Prize-winning playwright Michael Cristofer, who wrote a screenplay for this film that got rejected, said the experience working on this film was an ugly one.

The movie is notable for Robert Downey Jr.'s performance playing a drug addict with Downey off-screen having a real-life drug addiction.

The producers and 20th Century Fox studio executives frequently argued about amount of decadence that would be depicted in this movie with the film being "meetinged to death" as the New York Times reported.

Producer Marvin Worth in June 1985 first optioned the film rights to Bret Easton Ellis' then unpublished "Less than Zero" novel by purchasing an option for the small amount of US $7,500 on the proviso that the 20th Century Fox film studio would make the movie.

Filmed at the Scream nightclub (near the 1:02 mark). The "Scream" was a popular nightclub during the 1980s, catering to the Glam Rock, and Goth genres, particularly during the mid 80s, boasting three bars, stage for live music, movie theater, coat-check, video room, blacklight hallway and dance floor (located upstairs). Getting to the upstairs rooms required braving a two-story climb that lined the outside of the building.

Pulitzer Prize-winning playwright Michael Cristofer to write the screenplay. He stuck close to the tone of the novel and had Clay take some drugs but did not make him bisexual. The studio felt that Cristofer's script was too harsh for a commercial film.

The movie is sampled in Bryce Vine's song "Glamorama".

The studio wanted to appeal to Andrew McCarthy's teenage girl fans without alienating an older audience.

The movie was filmed during May, June and July 1987.

American and Hollywood directorial debut of British director Marek Kanievska.

Marek Kanievska was hired as director for two reasons and these were based on his direction of his critically acclaimed movie Another Country (1984). This was because Kanievska had in that movie (1) fashioned unsympathetic characters making them sympathetic and (2) been able to handle themes of bisexuality and sexual ambivalence.

Some of the film's english translations of this film's foreign film titles, according to the "Robert Downey Jr. Film Guide" website, were as follows: "Argentina: Corrupción en Beverly Hills (Corruption in Beverly Hills); Brazil: Abaixo de Zero (Less than Zero); Denmark: Livet i overhalingsbanen (Life in the Fast Lane); Finland: Alta Nollan (Under Nothing); France: Neige sur Beverly Hills (Snow on Beverly Hills); Germany: Unter Null (Under Zero); Israel: Young in Trap (English translation); Italy: Al Di Là Di Tutti i Limiti (Beyond All the Limits); Poland: Mniej Niz Zero (Less Than Zero); Spain: Golpe al Sueño Americano (A Blow to the American Dream); [and] Sweden: Noll Att Förlora (Nothing to Lose)".

Studio executives and Jon Avnet argued over the amount of decadence depicted in the film that would not alienate audiences. Larry Gordon, President of Fox, and who had approved the purchase of the book, was replaced by Alan Horn who was then replaced by Leonard Goldberg, who found the material distasteful but Barry Diller, the Chairman of Fox, wanted to make the film.

The movie was the first filmed adaptation of a written work by Bret Easton Ellis with the movie's source "Less Than Zero" book being Ellis' first novel as well.

There is speculation that the character Clay Easton was based on Bret Easton Ellis himself and that the events in the novel reflect the real life experiences of the author.

According to the IMCDb, the make and model of Clay Easton (Andrew McCarthy)'s car, the film's signature vehicle, was a red 1956 or 1957 Chevrolet Corvette [C1] convertible; it's actually a 1959 C2.

James Spader and Robert Downey Jr. also starred together in Tuff Turf (1985). They would later reunite in Avengers: Age of Ultron (2015).

Second of two movies featuring actor James Spader and actress Jami Gertz. The first had been Brooke Shields' movie Endless Love (1981) made and released about six years earlier.

Marek Kanievska was hired to direct because he had dealt with ambivalent sexuality and made unlikeable characters appealing in his previous film, Another Country (1984). Jon Avnet felt that Cristofer's script was "so depressing and degrading." Avnet instead wanted to transform "a very extreme situation" into "a sentimental story about warmth, caring and tenderness in an atmosphere hostile to those kinds of emotions".

In one of Brad Pitt's first roles as an extra, during a take Brad added his own unscripted line of dialogue in order to get a SAG (actor's union) card. The director yelled cut and he was told if he did it again he would be fired.

Star Billing: Andrew McCarthy (1st), Jami Gertz (2nd), Robert Downey Jr. (3rd) and James Spader (4th).

Harley Peyton completed three drafts of the script. In his version, Clay Easton is no longer amoral or passive. The studio still considered the material edgy and kept the budget under $8 million.

Clay's last name, not given in the book, is said by Julian to be Easton, a reference to the author of the novel, Bret Easton Ellis.

Robert Downey Jr.'s father in this movie is also the father in Risky Business (1983).

Brad Pitt: Uncredited, as an extra/background artist portraying a preppy guy party-goer and seen as Clay Easton enters the party at the movie's beginning.