The movie is based on a young adult science fiction novel by Pittacus Lore, and it is the first book in the Lorien Legacies series: "I Am Number Four," "The Power of Six," "The Rise of Nine," "The Fall of Five," "The Revenge of Seven" and "The Fate of Ten." The final book in the series was released in 2016.

Teresa Palmer went through three months, four hours a day, six days a week of exercises prior to filming. It included training for sword work, flips, sword fighting and wire work.

The studio tried to recreate the success of Twilight (2008) with this film by marketing it as a "Twilight for boys." Although it hoped to be a box office success, the movie did not earn the hundreds of millions that the Twilight films (2008-2012) grossed.

Karen Allen filmed scenes as Sam's mom, but they were deleted from the film.

Alex Pettyfer and Dianna Agron started dating while filming this movie. They broke up a day after the film was released in theaters.

Dianna Agron landed her role after a chance meeting with executive producer Steven Spielberg at a charity event. As a big fan of Glee (2009), Spielberg was seriously considering Agron for a prominent part when the chance encounter proved beneficial for both parties.

The evil aliens in the film are called "Mogadorians," and are apparently from the planet "Mogadore." Mogadore also happens to be a small suburb of Akron, Ohio, not far from where the film takes place and not far from where James Frey, one of the writers of the novel on which this film was based, grew up.

Just like the aliens are from Mogadore, which is their planet, but also a play on the small Ohio town of the same name, the planet which John and Number Six are from, Lorien (pronounced LORE-ee-en), is a play on the small Ohio town of Lorain (pronounced lo-RAIN), which is about one hour northwest of Akron.

As stated in the goofs, the sheriff uniforms are incorrect, but on top of that, the U.S.A. flag on their jackets' shoulder faces forward. While there is technically no wrong way to wear the American flag on a uniform according to the U.S. Flag Code, most law enforcement agencies follow the practice of the U.S. Army, which, when wearing the flag on a sleeve, orients the blue star field to the front of uniform.

Sharlto Copley was cast as Henri, but dropped out due to scheduling conflicts.

As Henri digs into the disappearance of Sam's dad and what he found at the closed ore mill, the camera pans over what appears to be a map of earth but is actually the continents drawn on a star chart. Then, the eye-like symbol with nine circles Henri had been standing on in the mill, with lines through it and Earth locations written with latitude and longitude coordinates. 1) Malaysia - The coordinates are for Taman Negara, a national park. 2) London - a point on the south bank of the Thames just east of London City Airport. 3) Africa - A spot in the Sahara Desert, near Libya's east border with Egypt. 4) Florida - The first number in the longitude is difficult to read, before the decimal point, but for Florida it should say *negative* 80. That spot is in the water near Key West.

The license plate that is burned in the beach fire is a Florida plate; the license plate that Henri replaces it with is a New Mexico plate.

First DreamWorks Pictures film to be distributed by Walt Disney Studios Motion Pictures (through Touchstone Pictures).

Several of the ending plot points were set-ups for a potential sequel, including: coming back to Sarah in Paradise, Sam being "one of us now," the search for Sam's real father, what is in the box, and more.

Number Six's motorcycle is a Ducati 848.

Right before he dies, Henri (Timothy Olyphant) tells Number Four, "You have no idea what you are capable of." Timothy Olyphant uses almost the exact same line in Live Free or Die Hard (2007) when he tells John McClane, "You have no idea what I am capable of."

Sarah's passion for photography complements Four's/John's powers, in that both traditional photography (using film, as Sarah does) and John's first powers are essentially based on controlling light.

During the scene, where John and Sarah, are in the Haunted Hayride, there is a sign that reads, "Your Number's Up', and it is a reference, to the individual characters, that have already died, (Number 1, Number 2, Number 3)