Ever since The Boy Who Lived came to the big screen in 2001, movie studios have been clamoring to find the next “Harry Potter.” “Ender’s Game,” which is based on the Orson Scott Card book in which a brilliant child name Ender Wiggins is recruited and trained to fight in an intergalactic war in order to save the earth, is the next in a long line of movies trying to take a successful young adult book series and turn it into a cash-cow franchise.

No matter how you slice it, adapting a beloved book into a movie is difficult. From the “Hunger Games” to “50 Shades of Grey,” there is usually a large amount of outcry from readers before they even start production, over everything from casting choices to filming locations.

No matter how detailed an author’s description of a character or a setting is every reader is going to imagine it differently. This makes it impossible for directors to bring a book to life on screen in a way that will please every fan.

Similarly, screenwriters are tasked with squeezing hundreds of pages worth of content into a two-hour movie. They have to make the movie entertaining and understandable to those who are not familiar with the original source material and still make it a faithful interpretation for hardcore fans.

Gavin Hood (“X-Men Origins: Wolverine”) pulled double duty as director and screenwriter for “Ender’s Game,” and unfortunately both his direction and script seem to be lacking the thing that made “Harry Potter” such a phenomenon: heart.

The premise of this film is interesting and yet very familiar, children being trained to fight in a war is something we have seen in both the Potter films and the very popular “Hunger Games” series, but this big-screen adaptation feels more like an outline of the source material, with things being stated rather than shown and scenes rushing by so quickly that there is no chance to absorb any sort of emotion out of the scene.

Asa Butterfield (“Hugo”) does a valiant effort at carrying the movie as the title character Ender, and though he won’t go down in great child actor history like Dakota Fanning or Haley Joel Osment, he certainly has potential to grow into a great leading man. However, Butterfield is never given a chance to show much range due to the clunky script and short scenes. He’s left explaining how he feels while Harrison Ford (“Star Wars”) tells us how great Ender is without much chance for us to see it ourselves.

Ender’s friends and battle-school classmates are reduced to being Mighty Ducks-esque side characters that have a few comical or encouraging lines but not much else left to do. It makes it hard to be invested in them if viewers know nothing about them. One of the things “Harry Potter” did so well was that it made viewers fall in love with even the smallest of characters. Neville’s triumph in the end was just as exciting as Harry’s.

It’s hard to see this film turning into a classic that calls for repeat viewings every time it is on ABC Family, but every series has room for improvement. If they move forward with more big-screen adaptations, then the creators need to spend more time fleshing out the characters and focusing on the emotional turmoil these child soldiers are facing by actually giving them the chance to act.