Val Kilmer walked around in a $500 pair of Louis Vuitton driving shoes and wore nail varnish while experimenting with several variations of speech patterns for the role. Kilmer also noted this was done much to his son Jack's chagrin.
Val Kilmer met Robert Downey Jr. for the first time at a Hollywood party. A week later he received the screenplay for Kiss Kiss Bang Bang (2005) and agreed to do it before he'd even finished reading it. Upon agreeing, and much to his delight, he was informed that Downey Jr had already been cast.
Warner Brothers were willing to produce the movie with a larger budget if Harrison Ford were to play the detective. When he passed, several other options were briefly considered before Val Kilmer was offered the role.
Shane Black had been suffering from writer's block; it ultimately took him over a year and a half to write the script for Kiss Kiss Bang Bang (2005). He then had enormous trouble trying to sell it. His former cachet as being the highest paid screenwriter meant nothing when he was touting around his screenplay. Eventually he took it to Joel Silver who gave him his first break back in 1987 when he bought Lethal Weapon (1987).
Shane Black read several stories by Raymond Chandler when writing this script. As a result, the story is divided into chapters and the chapter titles come from Chandler works. Specifically: 1. "Trouble is My Business", 2. "The Lady in the Lake", 3. "The Little Sister", 4. "The Simple Art of Murder", and Epilogue: "Farewell, My Lovely".
Joel Silver noted that the film was originally budgeted at US$10 million because Warner Bros. were not confident in the premise. The film ran over and the final budget was US$15 million. Warner Bros. loved the film when it was screened, and immediately opened it at the 2005 Cannes International Film Festival in a high profile capacity.
The phrase "kiss kiss, bang bang" appeared in the 1960s as an overseas slang for spy movies, especially James Bond movies. It was popular in Europe and Japan. It first appeared as a film title for Kiss Kiss - Bang Bang (1966), a 1966 spy comedy made in Spain with Italian financing. It was also the title of famed critic Pauline Kael's second published collection of reviews. Kael wrote that she chose the words as her title because they are "perhaps the briefest statement imaginable of the basic appeal of movies."
In reference to the "Ike, Mike, and Mustard" quote. Ike and Mike are diner slang for salt and pepper shakers. Also, Pre-1950s, an "Ike, Mike, and Mustard" joke was an off color joke, generally with sexual references, that wouldn't be told in polite or mixed company.
The movie's title is a reference to an un-used theme song to the James Bond movie Thunderball (1965). "Mr. Kiss Kiss Bang Bang" was recorded by first Shirley Bassey and then Dionne Warwick after composer John Barry had chosen the title when he read a magazine article which mentioned that was how Bond was known in Italy. However, the producers got cold feet at the last moment and asked him to write a title song, "Thunderball", which was performed by Tom Jones. Both versions of "Mr. Kiss Kiss Bang Bang" were released many years later, and "Kiss Kiss Bang Bang" has since become a slang description of the James Bond-style spy genre.
At one point in the film Gay Perry (Val Kilmer) reveals that Colin Farrell is up for the role that Harry is auditioning for. Kilmer had previously played Philip, father of Alexander the Great (Farrell) in Alexander (2004).
In one scene, Harry Lockhart is prompted to read lines from a script sample. The first line he reads ends with the phrase "go spit," which is also a catchphrase of the Roger Murtaugh character in the Lethal Weapon (1987) movies written by Shane Black.
The trivia item below may give away important plot points.
Corpse count: 12: Richie (shot by woman on fire escape); Veronica Dexter (the "lady in the lake"); Jenna Lane (suicide); Mr Frying Pan (shot by food stand owner); Pink Hair Girl (shot by Mr Fire); Mr Fire (shot by Harry); Dexter's Clinic guard (shot by Harry); Aurelio (shot by Perry); Dexter's goon on bridge (shot by Perry); Harlan Dexter (shot by Harry); two goons on freeway (shot by Harry).