Although cut from the theatrical run, Captain America can be seen in the alternate beginning on the DVD and Blu-Ray. When the last piece of ice breaks up toward the screen, hit the pause button. There, frozen in the ice, lays Cap with his shield.
In a deleted scene Blonsky describes the Hulk to General Greller: "8 foot, 1500 pounds easy... and green. Or gray, sir. Greenish gray.. It was very dark, I couldn't tell." This is a reference to the Hulk being gray in his first comic appearance. Problems with the gray coloring in the first issue led to his skin color being changed to green.
Edward Norton, who had previously rewritten films he starred in, wrote a draft of the script which Louis Leterrier and Marvel Studios found satisfactory in establishing the film as a reboot of Hulk (2003). As Norton explained, "I don't think that in great literature/films explaining the story's roots means it comes in the beginning. Audiences know the story, so we're dealing with it artfully." Norton's rewrite added the character of Doc Samson and mentioned references to other Marvel Comics characters. He also wanted to put in "revelations about what set the whole thing in motion" that would be explained in future installments.
The live news footage from the Culver University incident can be in the SHIELD office in Iron Man 2 (2010), placing the events in the second half of this film after the events in Iron Man 2 in the timeline.
There are references in the film to Marvel Comics' next film, Captain America: The First Avenger (2011). Firstly, there is a portrait of Steve Rogers, the original Captain America, seen in the General Ross's office. Next, a label can be seen on the storage tank reading: "Dr. Reinstein." Reinstein was the doctor who developed the Super-Soldier serum that transmogrifies Rogers into the Captain. Louis Leterrier mentions he shot a scene where Banner encounters Captain in the Arctic, but it was cut out of the final cut of the film. It is on the special features options of some DVD editions, however.
The Hulk's look was based on comic book artist Dale Keown's drawings, where "the Hulk, being beyond perfect, has zero grams of fat, is all chiselled, and is defined by his muscle and strength so he's like a tank."
In the scene where Bruce Banner emails Mr. Blue with his data while Betty purchases the used truck, the email is tracked through the Strategic Homeland Intervention Enforcement Logistics Division (S.H.I.E.L.D) database.
Paul Soles who portrays "Stanley", the owner of the pizza shop, provided the voice for Dr. Bruce Banner in the 1960s Hulk (1966) animated series. The character's name may also be another tribute to Hulk co-creator Stan Lee.
Stylistically, the filmmakers chose a darker shade of green from Hulk (2003), and decided to not make him as large. His size does not increase as he becomes further enraged, staying at a consistent height.
Although director Louis Leterrier liked Hulk (2003), he concurred with Marvel Studios that to continue the franchise it would be better to deviate from Ang Lee's cerebral style from the first film and focus on a more action-filled tone. He also believed that in keeping with Hulk (2003)'s poetic feel, the VFX were mostly "a fluorescent-green guy who was simply flying around; he had no weight and was too smooth-looking," so he wished to make the film's VFX grittier and darker "and perhaps even a little scarier!"
After the Hulk appears at Culver University, two students are interviewed in the news, named Jack McGee and Jim Wilson. Jack McGee was a tabloid reporter who attempted to track down the Hulk in The Incredible Hulk (1978), and in the comics Jim Wilson was a young orphan who befriended the Hulk.
In Germany the film was cut for a more commercial "Not under 12" rating. However, these cuts were done so clumsily that not only movie buffs but also average movie goers noticed them which resulted in lots of complaints to theater owners. To apologize for this some cinemas gave away free movie tickets to the complaining customers. Additionally many cinemas, including some of Germany's largest cinema chains, included warning messages on their websites to raise awareness of the issue.
In the comics, the Abomination possesses pointed ears. Louis Leterrier wanted this characteristic to appear in the film, but reasoned that the Hulk would bite them off (a la Mike Tyson on Evander Holyfield), which was considered too intense for a PG-13 film.
Visual effects supervisor Kurt Williams created special computer programs that controlled the inflation of muscles and saturation of skin color for the transformations (since Williams reasoned that skin color was influenced by emotions, like blushing for instance).
Edward Norton rewrote the script substantially and in certain posters, he was credited under the pseudonym of 'Edward Harrison'. Norton's writing credit was later denied by the WGA, and Zak Penn is the only writer credited.
The Hulk, as portrayed in this film, was created through a blend of motion capture and key frame animation (by Rhythm & Hues). Hulk (2003)'s VFX were carried out by Industrial Light & Magic, with its director Ang Lee providing motion-capture.
Tim Roth signed on the film because he was a fan of The Incredible Hulk (1978), as well as to please his comic-book-fan sons. On set, he constantly asked whether this would "be a cool shot" for his kids to see him in. He thoroughly enjoyed playing Blonsky, but found it difficult since to portray Blonsky's over-the-hill state he could not work out; but he hired a personal trainer to assist him in motion-capturing the Abomination's movements.
The film joined Toronto's Green-Screen initiative, to help cut carbon emissions and waste created during filming. Hybrid and fuel-efficient vehicles were used, with low-sulphur diesel as their energy source. For constructing the sets, the production department used a sustainably-harvested locally-sourced yellow pine, instead of the commonly-used lauan, and afterwards the wood was either recycled or given to environmental organizations. Paints with no/low volatile organic compounds were used, and paint cans were handed to waste management. A contractor was on set to remove bins. Environmentally-friendly items used on the set included cloth bags, biodegradable food containers, china and silverware food utensils, recycled paper, biodegradable soap and cleaners, rechargeable batteries and stainless steel mugs (one for each production member). Producer Gale Anne Hurd hopes the film will be a symbol of the drive to encourage less pollution from film productions.
Edward Norton and Tim Roth filmed their Hulk-Abomination fracases on a stage, using motion capture and 37 digital cameras. Roth enjoyed using the motion capture technique because it reminded him of fringe theatre.
In 2003, James Schamus had written a treatment for a direct sequel to Hulk (2003) featuring the Grey Hulk with The Leader and The Abomination under consideration as the lead villain. However, Universal at that time owns the rights to making the film and by the time the rights expired at the end of 2005, Marvel's own studio bought back the rights of making the movie with Universal only distributing it.
Louis Leterrier insisted Tim Roth, of whom he is a big fan, be cast as the film's main antagonist, even though Marvel Studios and Edward Norton were initially unsure of Roth as a supervillain. Leterrier later said "it's great watching a normal Cockney boy become a superhero!"
Near the beginning of the movie when Banner is flipping channels on the TV, one of the shows he stops on is "The Courtship of Eddie's Father" which starred Bill Bixby - Bixby is seen on the screen for several seconds. Bixby played The Hulk in the TV series - 1977-82.
The Hercules aircraft (337) at the beginning of the movie is stationed at 8 Wing Trenton, Ontario Canada. It is a Canadian Air Force plane flown by Canadian Military pilots. It was painted to resemble the USAF planes.
William Hurt was under consideration for the role of Gen. Robert E. Lee in Gettysburg (1993). Another role, that of Gen. John Buford, ended up being played by Sam Elliot, who played Gen. Ross in Hulk (2003).
The trivia items below may give away important plot points.
According to Louis Leterrier, the final scene (Banner grins as his eyes turn green) was a deliberately ambiguous shot: it was meant to show that Bruce finally learns to control the Hulk (for a Hulk sequel) or will become a menace (as the villain for the film The Avengers (2012)). Ultimately, the Hulk becomes a team player in "The Avengers" and Banner even reveals his secret of staying calm - he's always angry.
Tim Blake Nelson's character, Samuel Sterns, gets The Hulk's blood in a wound in his head. His head starts to mutate and then he smiles. This is a foreshadowing of his role in the sequel as the main villain, The Leader.
According to General Ross, the serum project that mutated Bruce Banner into the Hulk was developed during World War II. This is a reference to Marvel Comics' next film, Captain America: The First Avenger (2011), who was created with the use of a special serum. Additionally, the person who takes the serum must be treated with a unique form of radiation - any accidents or deviations from the procedure can cause horrific side effects to occur... as befalls Banner and Blonsky.
Zak Penn felt that the name "Abomination" sounded too silly, so Emil Blonsky is only referred to by his proper name. However, the word is used once when Samuel Sterns warns Blonsky that the mix of Banner's mutated DNA with Blonsky's injection "could be...an abomination."
In the comics, Emil Blonsky takes on a scaly reptilian appearance, becoming the Abomination. Louis Leterrier felt that while that was cool, it made no sense considering there was no reptile mix in his origin. So in this film Blonsky's appearance is redefined substantially to have his skin/muscles/bones exaggerated and sticking out all over his body. Leterrier describes Blonsky as "an uber-human, just like the Hulk, but a human who was injected with something in the wrong places and these places are growing differently." The VFX artists think of Blonsky as "a guy who transforms but is not used to having these new properties; for instance, he's much heavier, so when he walks down the sidewalk, he's tripping because his weight is destroying the sidewalk."
The Hulk's origin in this film is a combination of the Marvel Ultimates comics (experimenting on Captain America's super-soldier serum) and The Incredible Hulk (1978) (over-exposure to gamma radiation in an experiment). Even the equipment seen is a close match to that used in the TV series, right down to the light sliding over Banner's face.
Although the final scenes are set in Manhattan (Harlem to be exact), they were shot in Toronto, with the initial showdown between the Hulk and the Abomination being filmed on Yonge Street. Several Toronto icons are visible, most notably the "spinning disc" sign for Sam the Record Man, and the marquee of the Zanzibar Tavern.
In the Bruce Jones Hulk comics, Betty Ross aided Bruce Banner as a shadowy contact under the alias "Mr. Blue." Mr. Blue appears in the film, but is revealed to be Samuel Sterns. The title Mr. Blue is also a possible reference to Tim Roth's crime film Reservoir Dogs (1992), which featured Roth as Mr. Orange, and a Mr. Blue portrayed by Edward Bunker.