Ben Stiller said nearly all aspects of the Les Grossman character were developed by Tom Cruise, including the dancing and the look of the make-up. Stiller said that in addition to the more obvious make-up 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 that he had already developed for Natural Born Killers (1994).

Like his character, Kirk Lazarus, Robert Downey, Jr. is a method actor and stayed in character as Sergeant Osiris/Lazarus even while cameras were not rolling.

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 in this film because he felt wearing make-up to look African-American was offensive. Downey ultimately accepted the role because he liked the script and wanted to work with Ben Stiller and Jack Black.

The Southeast Asian gang Flaming Dragon, led by a pre-teen boy, was modelled after God's Army, a guerrilla army in Myanmar. The group was led by twin brothers Johnny and Luther Htoo, who were nine-years-old when it was founded in 1997. Johnny and Luther Htoo were fond of American action movie heroes, especially Rambo.

Owen Wilson was originally set to play Rick Peck. After his attempted suicide, Ben Stiller gave the role to Matthew McConaughey so that Owen could relax.

For the fake trailer "Satan's Alley", Tobey Maguire came in at the very last minute to film the role of Robert Downey, Jr.'s monk lover. He did it as a personal favor for Ben Stiller and Downey, his Wonder Boys (2000) co-star.

As part of a promotional tie-in, the "Booty Sweat" energy drink seen in the movie was available for a limited time on Amazon.

According to Robert Downey, Jr., the character Kirk Lazarus was based on a combination of Russell Crowe, Daniel Day-Lewis, and Colin Farrell.

Jeff "Fats" Portnoy was written with Jack Black in mind and was partially based on Chris Farley.

Ben Stiller originally planned to play Rick Peck, with Keanu Reeves playing Tugg Speedman.

Robert Downey, Jr. improvised many of his lines.

The water buffalo that Jeff Portnoy (Jack Black) rides turned out to be pregnant. The cast and crew found out it had been pregnant when they came to the set one morning and found her nursing a newborn calf.

Ben Stiller first came up with the idea for this film while working on Empire of the Sun (1987). He had 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, as well as how it made them feel like real soldiers. Stiller found this funny because he thought being an actor in a war film was nothing like being a real soldier in a real war.

Several disability advocacy groups criticized the "Simple Jack" subplot, a movie-within-a-movie in which Ben Stiller's character portrays a mentally disabled man. The film includes clips of the fictitious movie and re-enactments by Stiller. Scenes between Robert Downey, Jr. and Stiller drew particular scorn for their repeated use of the word "retard". Producers took down a "Simple Jack" website and proposed altering the movie in response to a special early screening for the disability groups in question, but they did not change the film. According to co-Writer Etan Cohen, the scenes were meant 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), as well as the actors who take these roles.

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, feeling that there were too many homages in the film at that point.

Jay Baruchel and Brandon T. Jackson had to be taught how to use a gun. Jack Black used an M-60, also known as "The Pig". According to his co-stars, he seemed very experienced.

Many have speculated that Tom Cruise based his performance as a vulgar movie mogul on Sumner Redstone. He and Cruise had a public falling out after Redstone had Paramount Pictures terminate their development deal with Cruise. His physical appearance was more than likely based on this movie's Producer Stuart Cornfeld.

Several actors and actresses made cameo appearances, including Tobey Maguire, Jennifer Love Hewitt, Lance Bass, Jon Voight, and Jason Bateman.

According to Ben Stiller, Tugg Speedman is partially based on a young Sylvester Stallone.

Although all the trailers seen in the film were for fake movies, there was one bit of real-life factual information. In the trailer for "Satan's Alley", Tobey Maguire was credited as an MTV Movie Award winner for "Best Kiss", which he actually won for Spider-Man (2002).

It was said by Jack Black himself that he first declined his role in this movie, due to the fact that he would have to color his hair blond. He soon changed his mind but was still not too pleased with dyeing his hair.

In one of the special features in the Director's Cut DVD, Ben Stiller said he had been developing ideas for this movie for about eight to ten 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 PTSD. 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 this movie.

Various characters mention that Kirk Lazurus is a five-time Academy Award winner. As of the film's release, Katharine Hepburn holds the record for most acting Oscars ever won, with four. No real actor, or actress, has ever won five.

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.

W. Earl Brown was offered the chance to audition for the part of Jeff Portnoy, but he turned it down because he knew it was written for Jack Black, and that Black was perfect for the role.

According to Ben Stiller, in an interview with Playboy, Jack Black filmed most of this movie with bruised ribs.

The Flo Rida hit "Low" played on the cell phone by Les Grossman was added during post-production after the song became a radio hit.

The film's title is a play on "Tropic Lightning", the nickname of the 25th Infantry Division, which has seen action in World War II, Korea, Vietnam, Southwest Asia and Iraq (among others). The division was the subject of The Thin Red Line (1998) and Platoon (1986). Famous members included Oliver Stone, Ice-T, and Track Palin, Sarah Palin's eldest son.

Kirk Lazarus' character says, "I don't break character until the DVD commentary is done." Sure enough, once the DVD commentary is completed, Robert Downey, Jr. starts talking like himself and breaks character.

During the party scene, following the video conference, Justin Theroux can briefly be seen as his Evil D.J. character from Zoolander (2001).

Kevin Hart was considered for the role of Alpa Chino.

The two characters played by Robert Downey, Jr. in the film are named Lazarus and Osiris, the names of two resurrected characters from ancient literature.

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").

During the battle scene near the start of the "film within the film", Jeff Portnoy (Jack Black), yells, "You call in that snake and 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-pound MK-81 "Snake-Eye" bombs, and 500-pound 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.

Whereas for this film, Ben Stiller planned to play a secondary character, but ended up playing the main character. The situation was the opposite for another film he directed, The Cable Guy (1997), in which Stiller planned to play the main character, but ended up playing a secondary character.

In the "never go full retard" scene, Kirk 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, Sellers was only nominated for Being There (1979), just like Penn for I Am Sam (2001).

In the film, Damien's surname "Cockburn" is pronounced phonetically (probably for humorous effect), whereas it is properly pronounced "Coh-burn".

Yasiin Bey was offered the role of Alpa Chino, but turned it down.

The character who starts spitting at Tugg Speedman is wearing a Coca-Cola t-shirt that says "drink Coca-Cola" in Hebrew.

Brandon T. Jackson's "Booty Sweat" commercial was the final scene filmed in the movie. On the DVD commentary, Ben Stiller remarked they shot it in the early morning hours of Thanksgiving. Once the filming wrapped, Jackson was escorted to the airport to catch a flight to Detroit to spend the holidays with his family.

Ben Stiller and Tom Cruise had also planned to team up on a Hardy Boys movie, which Shawn Levy was to direct, but it was scrapped, due to budgetary concerns.

The film cast includes two Oscar winners: Matthew McConaughey and Jon Voight; and four Oscar nominees: Robert Downey, Jr., Nick Nolte, Steve Coogan, and Tom Cruise.

In the "never go full retard" conversation, Lazarus notes that Sean Penn "went home empty handed" for I Am Sam (2001). The year of the Academy Awards where "Tropic Thunder" was eligible for nominations (and Robert Downey, Jr. received a Best Actor in a Supporting Role nomination for "Tropic Thunder") Sean Penn won the Best Actor Oscar for Milk (2008).

A giant "Om" sign from Hinduism can be seen in the office of Les Grossman. It could be intended to be ironic, given that the Om symbol is associated with peace and tranquility, which is the exact opposite of Les Grossman's character.

Co-Writer Justin Theroux said the film was easy to write because audiences have become aware of the process of film production.

Shipped to some theaters under the name "Capricorn".

The part of Rick Peck was written with Ben Stiller's friend and frequent co-star Owen Wilson in mind, but Wilson was involved in an apparent suicide attempt shortly before filming would've began and was still in recovery, so Matthew McConaughey, who is friendly with both Wilson and Stiller, stepped in to play the role.

The medicine that is used to darken Lazarus' skin is actually a bottle of a famous Chinese medicine that is used to heal bone injury. The name of the medicine is Yulin Zhenggushui, which means a medical liquor that heals bones, and is a product from Yulin, Guangxi, China, same province as Guilin.

Ben Stiller and Steve Coogan appeared in Night at the Museum (2006), Night at the Museum: Battle of the Smithsonian (2009), and Night at the Museum: Secret of the Tomb (2014).

In the movie, Kirk comments about "The Rain Man", which starred Dustin Hoffman and Tom Cruise, ironically Tom cruise plays the character of Les Grossman in this movie.

Robert Downey, Jr.'s character, Kirk Lazarus, bears a striking resemblance to Lakeith Stanfield.

Bill Hader and Mini Anden share the same birthday.

Robert Downey Jr. and Tobey Maguire play lovers in the fake trailer "Satan's Alley" within the film. They previously played lovers in Wonder Boys (2000).

Christine Taylor: Ben Stiller's wife appears at the awards ceremony, sitting a few chairs in from the aisle. She is briefly visible as the camera follows Tugg down the aisle. She also played Simple Jack's mother in the "Simple Jack" trailer.

Justin Theroux: The gunner on one of the Hueys in the beginning of the film. He also played the Zoolander (2001) D.J. at the One Week Down party in the Director's Cut.

Ben Stiller: [Star Trek (1966)] Speedman is seen watching clips from Star Trek: Arena (1967).

Cody (Danny McBride) seems to have won an Oscar for Best Visual Effects for the film-within-a-film. He holds it while applauding Tugg's Oscar win.

For all of the violent action in the plot, the only on-screen deaths are Director Damien Cockburn, the panda, and the bat.

Jon Voight's character is visibly angry when loses the Oscar to Tugg at the end of the film. This was a reference to Voight losing the Oscar to John Wayne in True Grit (1969) when he was nominated for Midnight Cowboy (1969).

The five 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 Voight in a nineteenth century drama, Sean Penn as a blind man, and Tobey Maguire for "Satan's Alley".

Tugg Speedman's celebration leap while holding his Oscar spoofs a similar antic by Cuba Gooding, Jr. after he won for Jerry Maguire (1996). Tugg's leap can be seen on the television screen behind Les Grossman, when Grossman is talking to his assistant and telling him a monkey could do that job.

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.

The movie Pulgasari (1985) is shown very briefly on Tugg's (Ben Stiller) iPod after he kills the panda in the jungle. The story behind Pulgasari's making signifies foreshadowing in Tropic Thunder (2008), as the filmmaker was held in North Korea for years to make movies for North Korean leader Kim Jong-il. Tugg Speedman is forced to re-enact "Simple Jack" while held captive.

The book (through which Rick Peck is skipping, when on the phone with Speedman) is "The Little Book of Big Breasts", a collection of artistic photos of well-endowed women. It was not a movie prop, as the book is real and is commercially available in both full-size and (slightly abbreviated) pocket editions. (Many editions have a black bra covering the breasts on the front cover.)