BEFORE COMING OUT as a militant, proselytizing homophobe, Orson Scott Card wrote one of the best science fiction books ever: 1985's Ender's Game, about a six-year-old boy who's Earth's last hope in a war with insectoid aliens derisively known as "buggers." In the film adaptation of Ender's Game, the aliens are, for obvious reasons, no longer called buggers—but much of the rest stays the same, starting when Ender (Asa Butterfield) is chosen by Colonel Graff (Harrison Ford) to join other children for relentless military training.

Written and directed by Gavin Hood—the director of the well-received Tsotsi and the execrable X-Men Origins: Wolverine—Ender's Game is a surprisingly faithful adaptation, considering Card's book is all but inadaptable. There are sacrifices—the kids have been aged up, the violence has been toned down, and a plot involving Ender's siblings has been cut—but Hood dutifully manages the basics: Here's Ender, getting beat up; here's Ender, winning some cool zero-gravity battles; here's Ender, a child tasked with saving Earth.

But dutifully managing isn't enough when the source material is this good. The visuals are impressive, Ford gives a decent performance for the first time in however long, and the battles are cool—but Ender's Game crams so much into so little time that none of it has any consequence. Alas, Card's book is about consequences. It's also a book that's profoundly, unforgettably sad—and sorrow is one emotion that Ender's Game: The Movie never conveys.

While Ender's Game boasts stuff worth seeing (ZERO-GRAVITY BATTLES), here's a downer: Anti-gay activist Card is credited as a producer on the film, which means he'll likely be seeing some money once Ender's Game makes back its budget. I was going to suggest buying a ticket to another film, then sneaking into Ender's Game, but here's a better idea: Swing by Powell's. Pick up a used paperback.

DEPT. OF CORRECTIONS: Following this review's publication, it was revealed that Orson Scott Card will not directly profit from the Ender's Game movie. More details here.