|Ender's Game movie poster.|
Here's a one-sentence description of the film from the Internet Movie Database: "Young Ender Wiggin is recruited by the International Military to lead the fight against the Formecs, a genocidal alien race which nearly annihilated the human race in a previous invasion." You can learn more about the basic plot from the book description (click the Amazon link below), so I won't bother explaining.
The movie stars Asa Butterfield as the protagonist boy Ender Wiggin, Harrison Ford as Colonel Graff, Hailee Steinfeld as Ender's friend Petra Arkanian, and Abigail Breslin as Ender's sister Valentine Wiggin among others. It's based on the book of the same name, which won both the Nebula and Hugo awards. If you haven't read the novel, you should read it. Below is a Kindle e-book version of it. (I usually prefer the Nook versions because I like the epub format since it's free of Digital Rights Management, but the publisher actually requested that the Kindle version be free of DRM restraints, and Amazon complied.)