Assassin's Creed is about a corporation who wants to unlock history's dark secrets. They plan on achieving it by using a device called the animus that uses the blood of the target's descendant to create a virtual environment of the ancestor's memory. The corporation is run by the Templars and their counterpart are called the Assassins.
Having played most of the games in the video game series, I felt this was a pretty lack luster attempt at capturing the story. Nothing is really explained in great detail like in the games, which was unfortunate but I can give it a pass since I shouldn't expect a movie that is only two hours long to explain too many of the secrets. What I can't forgive is the fact they continually addressed the apple over and over again but never explained its full significance. The scenes that took place in the past almost felt unnecessary as it never really furthered the plot.
All of the characters seemed pretty uninteresting... well at least compared to their video game counterparts. I honestly can't go into detail about them as most of their dialogue was just short sentences. They never became good three dimensional characters but instead cardboard cut outs of Desmond, Lucy, and Warren. The movie was just one long trailer for the games which granted was Ubisoft's intention and they didn't hide that fact. They pretty much even said before the movie was released that Assassin's Creed will not be a great film. The main goal is to get more people into the game series. That is my take away from this movie, Assassin's Creed is so vague in the story and characters that casual movie goers will be thinking "you know what, I didn't learn anything from this movie but I want to. Maybe I should try the game."
If you are a fan of the series, especially if you enjoyed the events that took place in the present. I expect you will be disappointed in the movie. If I were to put the movie on the video game scale, I would say it was better than Unity (by far) and would be even with Syndicate.
Assassin's Creed is definitely not a movie that you need to see in the theaters. It is more of a movie that should be rented but even that I am unsure about as I type this.