In order to deal with the constant bustle of Hong Kong, director Paul McGuigan and the crew decided to shoot the film "guerilla-style", with the cameras hidden in vans, filming through small holes, and the actors doing their scenes in one take on the streets.
The different type of psychics in the film are: - Movers (move objects with their minds.) - Pushers (control other peoples' thoughts.) - Watchers (see the future.) - Bleeders (emit high-pitched screams that can burst blood vessels.) - Sniffs (track people and objects.) - Shifters (temporarily change what an object looks like to others.) - Wipers (wipe memories.) - Shadows (cloak themselves and others around them from detection.) - Stitchers (heal or unheal people).
The idea of a government agency controlling people with special abilities for military and/or intelligence uses is in fact inspired by real-life experiments of the US government, particularly the long-running Stargate Project.
Director Paul McGuigan tried to limit the use of digital effects as much as possible, recalling the great directors who didn't have such means available to them yet made up for them with their imagination. In fact the only scenes in which green screens were used were the car chases, as Hong Kong traffic is very heavy.
In Greek mythology, it was Cassandra who was given the gift of prophecy, but also cursed so that no one would ever believe her. In this movie, it is Cassie who is able to see the future but has a hard time convincing those around her.
In the hotel scene where Nick and Kira hook up, the script called for Nick (Chris Evans) to touch Kira's (Camilla Belle) butt while they kissed. On set, Chris Evans refused to touch Belle without her permission. Belle ended up giving Evans permission and the scene was filmed as scripted.
Director Paul McGuigan was much more interested in the character element of the picture than in its action element, stating that though it was an action movie, the characters were very developed, much more so than in most such genre films.
In Spanish (at least in Chile), the movie was renamed as "Heroes" at the cinemas, which led to confusion to moviegoers who were expecting some relation with Heroes (2006), the TV series. Both the movie and the series tell the story of a group of people with super-powers being chased by a secret organization.
The choice to shoot the film in Hong Kong was inspired by the classic film Casablanca (1942). Indeed, director Paul McGuigan explains that in the thirties and forties, Casablanca was a den for scoundrels and the perfect place to hide as everyone could go there. To the makers of the film, Hong Kong was the 2000's equivalent to Casablanca.
The subject of the film piqued director Paul McGuigan's interest and led him to find out all that he could about it on the Internet, some of which he found quite incredible, notably in the experiments conducted during the Cold War by both the Soviets and the Americans.
There are several actors from comic book films and TV series in this movie * Chris Evans plays Steve Rogers/Captain America (Captain America: The First Avenger, The Avengers, Thor: The Dark World, Captain America: The Winter Soldier, Avengers: Age of Ultron, Ant-Man, Captain America: Civil War). He also played Johnny Storm (Fantastic Four, Fantastic Four: Rise of the Silver Surfer). * Corey Stoll plays Darren Cross/Yellowjacket (Ant-Man) * Djimon Hounsou played Korath the Pursuer (Guardians of the Galaxy) * Ming-Na plays Agent May (Agents of S.H.I.E.L.D).
The trivia item below may give away important plot points.
When Kira Hudson (Camilla Belle) opens the red envelope on the plane at very end of the film, it contains a picture of Nick Gant (Chris Evans) and herself in front of the Coney Island Cyclone roller coaster, with "kill him" written on the left, and "see u soon nick" written on the right.