Steven Spielberg (a producer of the production) was reportedly on set many times throughout the course of filming. Director J.J. Abrams and Spielberg have both gone on record stating that the filming of this production was some of the most fun they have ever had on set.
Riley Griffiths (Charles Kaznyk) played an April Fool's prank on director J.J. Abrams during filming: "On the verge of crying, I told him I had lost my script, lost it at a mall in L.A., somebody took it, and it's online. He totally fell for it... I think I might have been more scared than J.J. I was trembling."
Originally, when the boys were sitting and waiting for Alice to pick them up, they were supposed to just talk. However, J.J. Abrams heard the boys singing together between takes later on, and re-shot the scene featuring them singing "My Sharona."
It was very difficult for Joel Courtney to film the scene where he had to yell at Kyle Chandler (who played his father). Since Joel was naturally very quiet, J.J. Abrams had to coax him into yelling loud enough.
J.J. Abrams originally had two separate ideas for his follow-up to Mission: Impossible III (2006). One was a coming-of-age story, the other was an alien on the loose idea. It was much later in development that he actually had the idea to combine the two.
In the summer of 2010, Joel Courtney visited his brother, an aspiring L.A. actor, attended one of his brother's acting classes, fell in love with acting, auditioned for a tvscommercial in LA, was urged by an acting coach to answer a J.J. Abrams casting call, and after eleven call-backs landed the lead role of Joe Lamb.
The first teaser for the film was shot by cinematographer Wally Pfister, Christopher Nolan's frequent collaborator, months before principal photography began. Larry Fong was later brought aboard for the actual shoot.
J.J. Abrams named the film's fictional setting, Lillian, Ohio, after his grandmother. The map showing where runaway dogs were found shows it located on the north side of route 35 ten miles west of Dayton (twenty-two miles west of Wright-Patterson Air Force Base).
Since the kids were making a zombie movie, there are several references to director George A. Romero. For example, Romero Chemicals as the evil company, plus the poster for one of his movies in Joe's bedroom and reference on the radio.
In the Snack Shack Diner scene where the kids are talking amongst themselves about the train wreck, Deputy Lamb can be seen through the window getting out of his patrol car at the auto dealership because, as it was originally written, the diner scene and the auto dealership scene took place simultaneously but during editing the dealership scene was moved to later.
The gasoline station on the outskirts of town is named Kelvin Gasoline. Kelvin was the name of J.J. Abrams' grandfather. Abrams commonly uses this name in his work, such as "Kelvin Inman" from Lost (2004) and the USS Kelvin from Star Trek (2009).