the director is sam liu, who has directed prior dc animated films. the story was written by eric carrasco, partnered with jim krieg and alan burnett. the film features kevin conroy, susan eisenberg, and george newbern reprising their roles as batman, wonder woman, and superman from "justice league" and other dc productions. originally, the film was set to use the phil bourassa art style and models from "", with the voice cast already having done their recordings. however, to avoid confusion with the new 52-based dcamu movies, the film used the animation models from "justice league unlimited." the main title themes from "", "", and "justice league unlimited" are included in the score by composers mccuiston, ritmanis & karter (all dcau alumni) to represent their respective characters.