In the film, Kirk Lazarus says "I don't drop character 'til I've done the DVD commentary." When recording the audio commentary for the unrated DVD and blu-ray, Robert Downey Jr. actually spends the entire commentary in the character that appears on the screen as the movie progresses.
Robert Downey Jr. was very reluctant to take the role because he felt wearing the make-up to look African-American was offensive. But Downey later accepted the role because he liked the script and wanted to work with Ben Stiller and Jack Black.
Ben Stiller says that nearly all aspects of the Les Grossman character were developed by Tom Cruise, including the dancing and the look of the makeup. Stiller said that in addition to the more obvious makeup effects applied to Cruise's face and head, and the extra hair on his chest and arms, Cruise also decided to play the character wearing oversized prosthetic hands.
The character of Kirk Lazarus was originally written as Irish. It was changed to Australian, when Robert Downey Jr. said it would be easier for him to improvise in the Australian accent he had already developed for Natural Born Killers (1994).
The South Asian gang "Flaming Dragon" has a pre-teen boy, Tran, as its leader. This is modeled after a guerrilla army in Burma/Myanmar called "God's Army". Their leaders were a pair of twin brothers, Johnny and Luther Htoo who were about 10 years old at the time of the group's founding. Johnny and Luther had a fondness for American action movie heroes, especially the Rambo franchise.
The movie drew criticism from several disability groups for the "Simple Jack" subplot, regarding a movie-within-a-movie in which Ben Stiller's character portrays a mentally disabled man. Clips of the fictitious movie are shown, and re-enacted by Stiller, while scenes between Robert Downey Jr. and Stiller drew particular scorn for their repeated use of the word "retard". The producers withdrew a "Simple Jack" website, and proposed altering the movie in response to a special early screening for the disability groups in question, but did not follow through on the suggestion. According to co-writer Etan Cohen, the scenes were not meant to derive humor from mental disability itself, but to satirize emotionally exploitative depictions of mental disability in movies such as Rain Man (1988), Forrest Gump (1994), I Am Sam (2001), and Radio (2003), and the actors who take these roles.
Throughout the film it is mentioned that Kirk Lazurus is a five-time Academy Award winner. As of the film's original release, Katharine Hepburn holds the record for most acting Oscars ever won with four--no real actor has ever won five.
Ben Stiller first came up with the idea for this film while working on Empire of the Sun (1987). He has said in interviews that at the time he had friends who were actors in Platoon (1986) and Hamburger Hill (1987) and they would go on about the intense "boot camp" preparation and simulation of war these projects involved and how it made them feel like real soldiers. Stiller found this funny because he thought that being an actor in a war film was nothing like being a real soldier in a real war.
The title is a play on "Tropic Lightning", the nickname of the 25th Infantry Division which has seen action in WWII, Korea, Vietnam, Southwest Asia and Iraq (among others). The Division is notable for being the subject of The Thin Red Line (1998) (based on James Jones's novel) and Platoon (1986). Famous members include Oliver Stone (who wrote and directed "Platoon"), rapper Ice-T and Ex-Alaskan Governor Sarah Palin's eldest son.
Many have speculated that Tom Cruise based his performance as a vulgar movie mogul on Sumner Redstone, with whom Cruise had a public falling out after Redstone had Paramount's terminate their development deal with Cruise. Regardless, his physical appearance is more than likely based on Tropic Thunder (2008) producer Stuart Cornfeld.
During the battle scene near the start of the "film within the film", Jeff Portnoy (Jack Black), yells, "You call in that snake 'n' nape and get us some boom-boom NOW!" Used extensively by American forces during the Vietnam era, "snake and nape" was a close air support ordnance made up of 250-lb. Mk-81 "Snake-Eye" bombs and 500-lb. M-47 napalm canisters. Essentially, Jeff Portnoy's character "Fats" was telling the radio operator to call for airplanes to come in and drop a combination of conventional bombs and napalm on the enemy so the wounded could be evacuated.
It took fifteen takes to get Steve Coogan's nose to bleed during the video conference scene with Tom Cruise's character. Each actor's part was filmed separately, with Justin Theroux serving as Cruise's stand-in during Coogan's filming.
In one of the special features on the director's cut DVD, Ben Stiller said he has been developing ideas for this movie for about 8-10 years. One of his first ideas was that the movie was going to be about actors going to a "fake boot camp" for a couple of weeks and coming back with Post Traumatic Stress Disorder. When Stiller started out in Hollywood, he had a lot of colleagues going into war movies and they would attend a "fake boot camp" in order to prepare for their roles. He found it ridiculous and this was an early inspiration on what would become Tropic Thunder (2008).
Originally Nick Nolte's reveal during the video teleconference scene was intended to be an homage to Robert Shaw's character of Quint in Jaws (1975). Ben Stiller toned it down because he felt there were too many homages in the film at that point.
Although all the trailers seen in the film are for fake movies, there is one bit of real-life factual information. In the trailer for Satan's Alley, Tobey Maguire is credited as an MTV Movie Awards Best Kiss winner, which he actually won for Spider-Man (2002).
The poster for "The Fatties" behind Jeff Portnoy (Jack Black) in the trailer features the names of a few of the film's actual crew members: costume designer Marlene Stewart, editor Greg Hayden, director of photography John Toll, and screenwriter Justin Theroux. In addition, the poster contains the DreamWorks Pictures logo, the Dolby Stereo logo, and a fictional composite of several MPAA ratings (reading "PG - Parental Guidance - under 11 requires accompanying parent or guardian").
In the "never go full retard"-scene, Kirk (Robert Downey Jr.) cites Peter Sellers performance in Being There (1979) as a good example of how to avoid missing out on an Oscar by going "full retard", as opposed to Sean Penn in I Am Sam (2001). In reality, Peter Sellers was only nominated for Being There, just like Sean Penn for I Am Sam.
Ben Stiller's wife appears at the awards ceremony sitting a few chairs in from the aisle, seen for an instant as the camera follows Tugg down the aisle. She also plays Simple Jack's mother in the 'Simple Jack' trailer.
The four actors nominated for Best Actor in a Leading Role are Tugg Speedman, Tom Hanks, Sean Penn, Tobey Maguire, and Jon Voight. Tom Hanks appears to have been nominated for playing a handicapped contestant in the Special Olympics, Jon Voigt in a 19th century drama, Sean Penn as a blind man, and Tobey Maguire for the "Satan's Alley" seen at the beginning of the film.
Tug Speedman's celebration leap while holding his Oscar spoofs a similar antic by Cuba Gooding Jr. after he won for Jerry Maguire (1996). Tug's leap can be seen on the TV screen behind Les Grossman when Grossman is talking to his assistant and telling him a monkey could do that job. (Grossman is played by Tom Cruise, Gooding's Maguire co-star.)
WILHELM SCREAM] During the three-helicopter raid at the beginning of the film, when an enemy soldier is hit by gunfire and is blown backwards (elapsed time 6:04). Also, when Tugg Speedman throws "Half-squat" into the river in the finale. When this throw is repeated in the end credits, the scream is heard again.