Grant Morrison, writer of Justice League of America and Final Crisis among other things, teamed up with the director of Men in Black filmmaker Barry Sonnenfeld to animate the graphic novel.
According to the plot synopsis:
When aliens attack Earth, our planets only saviors are prehistoric beasts, which are more intelligent than humanity ever imagined.
For those unfamiliar with the medium, a motion comic combines elements of print comics with animation. It takes actual panels from the graphic novel and animates them slightly to give everything a "paper cut-out" puppetry feel.