In Gavin Hood's film adaptation of Orson Scott Card's sci-fi epic, "Ender's Game," the story sacrifices rich characterization in order to translate only the most vital plot elements.

Just like the 1985 dystopian classic, the humans beat the aliens thanks to a boy genius. But the intricacies of his genius – the complex tension between strategic brutality and a deeply loving empathy – are left largely out of the script.

In keeping with a general trend in American entertainment, "Ender's Game" revolves around planet Earth in the years after a devastating alien invasion. Millions were killed in the battle, but a brilliant pilot ended the invasion and literally saved the world. As hard as it may be to believe, nations join together to fund a hyper-technical International Fleet, sending billions of dollars into space to find the alien's home planet and destroy it before they return again.

The Fleet depends on a child training station known as Battle School, a space station packed with the most promising tactical prodigies of the known world. Ender, a wide-eyed 11-year-old played by Asa Butterfield, arrives at Battle School after proving his willingness to resort to violence in a particularly ruthless schoolyard brawl. He immediately faces alienation at the hands of Colonel Graff, a Harrison Ford-type principal played, predictably, by Harrison Ford.

Up to this point, Hood's on-screen version nails the character development necessary to attach the audience to Ender. As soon as Ender gets to Battle School, however, the director takes an all-too familiar approach, ditching characterization for the more scintillating options of explosions, gratuitous shots of Harrison Ford scowling and feel-good moments of Ender making friends.

The entertainment value skyrockets. The movie envisions Card's brilliant, zero-gravity battle game in a sexy, transparent globe; watching 11-year-olds engage in a very real war simulation while floating through space was much more enjoyable than watching the Vols engage in very bad football game Saturday night.

A techno-psychological "Mind Game" that Ender plays on the futuristic equivalent of an iPad also fascinates. Hood takes advantage of the virtual sequences, planting a few subtle references to the book for its fans while offering a more obvious stimulation to the moviegoers.

Despite the benefits of a movie screen, however, Ender's dual nature essentially disappears. We see him making friends as easily as a normal 11-year-old, when Card's original character struggles internally to manage his empathy and violence. Of course, the disappearance of internal thoughts is almost a necessity in the cinema medium; sans a narrator, we must settle for emoted thoughts rather than written down insights.

Losing these insights cripples the story, but even in this setback, the movie provides one crutch: Butterfield's depiction of Ender's inner conflict. The young actor manages to look like he's about to cry or murder at any moment, an impressive feat for the Hugo star.

Still, even an excellent actor cannot communicate the intricacies of an extensive novel. What we are left with in "Ender's Game" as a film is an entertaining, if shallow, visual experience.