(Photo: 20th Century Fox)

As with almost all adaptations, the Assassin's Creed movie will take some liberties in changing its story by comparison to its source material.

When Michael Fassbender's portrayal of Callum Lynch, a new character designed for the movie, the story will take place 65% in the present and only 35% in Animus-assisted 15th Century Spain according to the movie's executive producer Pat Crowley. This is a shift from the Assassin's Creed games which focused largely on telling the stories of the protagonists assassin ancestors.

"There are certain things that we absolutely want to respect in the game," Michael Fassbender tells IGN about the shift in focus, "but we also want to bring new elements to the game. This isn't a video game that we're making. We're trying to make a cinematic experience, so there are new things that we have to introduce."

Based on the trailer, Assassin's Creed looks like it remained faithful to the games enough to satisfy most of the franchise's biggest fans.

Assassin's Creed hits theaters on December 21, 2016.