...it's here where the movie stumbles (spoilers ahead). The premise is a damn good one: that Caviezel's (Jesus's) futuristic society got their genocide on when they invaded the alien's world, conquered it, and practically wiped out their entire species. Since Caviezel (Jesus) was a soldier in the army that committed these atrocities, we should feel like he's paying for his sins when the aliens begin to strike back.
This never happens. Caviezel's (Jesus's) character is constantly portrayed as compassionate and noble, and all the alien does for the run of the movie is sleep, stalk, kill lots of motherfuckers, and eat said dead motherfuckers. I felt no sympathy for the monster at all, which greatly reduces the impact of the final film.
My guess is that the writers had to drop most of this plot thread to accommodate the film's budget. The film was made for $47.5 million, but it looks like it was shot for half of that. The effects in the final film range from adequate to lousy, and it's only the creature's truly awesome design that saves the film, since the character is poorly rendered and animated for most of its shots.
Once the writers realized they didn't have the resources to fully create the struggle between the two species, they probably should have dropped this beat, but as a writer, I can't blame them for holding on to an idea that they were passionate about. None of this ruins Outlander -- it's still a solid fusion of action and horror. It's a great Friday night movie with friends. But it certainly never tops or trancends its origins.