An alien from the planet Lorien, Number Four (Alex Pettyfer) has come to Earth to hide from a vicious enemy known as the Mogadorians. Guided by protector Henri (Timothy Olyphant), Four is working his way through adolescence, finding himself in possession of several “Legacies” that offer him exceptional powers. Settling into a quiet life in the suburb of Paradise, Ohio, Four comes across fellow teen Sarah (Dianna Agron) at school, enchanted with her sense of kindness and photographic poetry. Unfortunately, there’s little time for love, as the Mogadorians, with their fearless leader Commander (Kevin Durand), draw near, forcing Four, human pal Sam (Callan McAuliffe), and huntress Number Six (Teresa Palmer) to fight back, working to gain full control over their Legacies.

Based on the best seller from author Pittacus Lore (a pen name for writers Jobie Hughes and James Frey), “I Am Number Four” has all the required ingredients for a modern teen movie. There’s a mysterious, hunky lead character of limited sexual threat and startling powers; huge amounts of knotted backstory with puzzling names and purposes to sort out (often unsuccessfully) during the course of the movie; and there’s a heavy fantasy angle that bleeds into swoony romantic yearn between two teens unable to consummate their love due to villainous interference. Certainly director D.J. Caruso (“Eagle Eye”) isn’t going to pooh-pooh any similarities made between “Twilight” and his film. Why throw away such amazing box office potential?

“I Am Number Four” is a children’s film, too frail to find an awesome voltage that would lend it a truly epic stance. Instead, it’s a surprisingly drab creation, following Four as he feels out the limits of his Legacies (interpreted here as glowing hands and telekinesis), deflects trouble from school bullies, goes all angsty on guardian Henri, and struggles to maintain a love connection with Sarah. It’s ultimately a protracted and uneventful origin tale, but that’s not made immediately clear, as Caruso seems to be building toward a colossal showdown between Four and the Mogadorians (goofy creatures who have gills located right next to their noses) for the future of Earth. The clash does finally arrive in the final act, but it’s an absolute snoozer set inside a high school, showcasing limp stunt choreography, unimpressive special effects, and truly random acts of CGI-laden heroism. “I Am Number Four” is a tease, promising muscular genre goods it never delivers, led by a painfully robotic performance from English actor Pettyfer, who spends the entirety of his screentime fussing with his unconvincing American accent.

With comatose cinematography, Durand cringingly overacting like a lunatic in the one-note villain role (he gives the same garish performance in every movie), and a script that’s sculpted solely for hardcore fans, “I Am Number Four” is often more irritating than involving. The kicker comes at the end, which really isn’t a satisfying conclusion, but a ballsy, shameless cliffhanger for a sequel. Caruso could’ve at least attempted a vague sense of finality to show some genuine respect to his audience, but closure won’t encourage people to follow Four again in a few years. Considering how uneventful the first installment is, I’d be shocked if we ever hear from these characters on the big screen again.

D+