Jonah Hill would perform plays at a local comedy club that drew crowds. One night, the children of Dustin Hoffman stopped by and found Hill to be hilarious. Hoffman's kids told Hill, "You should meet our dad." Hill did not know that their father was the famous actor, and was initially weirded out, nervously replying, "You should meet my dad." The next week, Hill was invited to dinner with the Hoffman family, and was gob-smacked when he realized that he was in the home of the legendary actor. Dustin Hoffman was impressed with Hill, and asked David O. Russell if he could have a part in the film. Russell said yes.
In one scene, Tommy harangues the Open Spaces group: "You have children in your own community who are going to prison. Father Flavin doesn't have the money to help them!" The unexplained reference is to Jim Flavin, a Boston-area priest who found Mark Wahlberg selling drugs on a street corner in 1987, turned him from a life of crime, and remains Wahlberg's good friend and adviser.
In March 2007, two videos appeared on the Internet showing on-set arguments between David O. Russell and Lily Tomlin. In one video, during filming of the office scene, Tomlin was annoyed at his direction, and Russell snapped, calling Tomlin several foul names and knocked over parts of the set. Dustin Hoffman can be seen walking away, hoping not to get involved. In the other video, while filming a scene in a car, Tomlin screams obscenities at Russell and gives him the middle finger. She also screams at Hoffman and Naomi Watts when they ask her to continue the scene. The car scene is not in the film. In an interview with the New York Times, Tomlin said "Adults have fights and go through stuff. I know some people are more dignified in the world, that if you transgress against that kind of professionalism, that it's some kind of great sin, but I don't see it that way."
Typically, David O. Russell would let the cameras continue rolling after the end of each scene, urging the actors to goof around and improvise. He felt this was the best way for them to lose any sense of self-consciousness. Jude Law and Dustin Hoffman later told him that they found it a very liberating way to work.
Four fictional websites were created for marketing the film, including ones for The Huckabees Corporation, an official website for the film's fictional chain store, and Jaffe & Jaffe, the existential detectives.
David O. Russell grew up in an atheist household, which gave him a spiritual curiosity that traveled with him through his adult life. When he went to Columbia University, he studied religion under metaphysical philosopher Robert Thurman, father of Uma Thurman. His theories of the essential and indissoluble oneness of everything in the universe can be read into the exchanges between Jaffe and Jaffe, the existential detectives in the film, played by Dustin Hoffman and Lily Tomlin.
Although she plays an airhead character in the film, a role she chose because it wouldn't overtax her, Naomi Watts nevertheless spent the first few days on-set in tears, as she was still living with the intensity of the character she had just played in 21 Grams (2003).
This was one of the first films to be shot with Panavision's 40-80mm AWZ2 (Anamorphic Wide-Angle Zoom) lens. At the time of filming, the lens was just a prototype; it would not be formally introduced until 2006.
Many theater managers mistakenly wrote the film's title on marquees and in showtime listings as "I Love Huckabees". This is most likely because on all promotional material, and in the film itself, the title is written with a heart symbol, instead of the word "heart".
The trivia item below may give away important plot points.
Naomi Watts, an Australian, plays the spokesperson for a fictional American supermarket chain. In the film, she is replaced by another wholesome all-American girl to represent the store, played by Isla Fisher, another Australian.