The first full trailer for Ender's Game, the film adaptation of the classic Orson Scott Card sci-fi novel, was released on May 7. The space adventure story was originally published in 1985, and it has surprisingly taken almost thirty years for this beloved tale to reach the big screen. But now, it's here.

Ender's Game stars sci-fi veteran actor Harrison Ford as one of the adults in the film, Colonel Hyrum Graff. Ford narrates the trailer. Humans are facing extinction from an alien race known as "buggers" and Formics. The military concludes that they need children, special children, to fight the hostile aliens. The search for and training of a child with special aptitude to lead the defensive force is a last-ditch effort.

Ender Wiggins, played by Asa Butterfield, is that child - humanity's last hope.

Ford, as Hyrum, says in the trailer, "We need a new kind of soldier, one who doesn't think the way we think, fear the things we fear, one the enemy would never expect. We need minds like yours, Ender."

Although Ender's Game is a young-adult story, the trailer attempts to convince adults that the film will provide quality entertainment. The trailer features plates that name the various actors that have received Oscars or Oscar nominations, an impressive list that includes Viola Davis, Ben Kingsley, Hailee Steinfeld, Abigail Breslin, and of course, Harrison Ford.

But the extra information is, for many fans of the book, unnecessary.

Tor.com's Chris Lough wrote, "Seeing the trailer as an adult evokes all the usual excited pulse-quickening reactions that these kinds of trailers do, but it's overlaid with the unsettling realization that you're getting excited about seeing children go to war. It leaves you tense and distinctly uneasy, which is a perfect evocation of what the plot of Ender's Game ultimately ends up doing. And if you've read the book and know what Ender is actually doing in this trailer then the unease ratchets up even more."

The trailer includes a link to the Tumblr for the film, which will have to tide fans over until its release.

Ender's Game will hit theaters on November 1, 2013. Check out the Ender's Game trailer below: