In the world of Legion, angels are not the cute cherubs with white little wings. Instead, they are tough SOBs that could be the perfect killing machines.
One such killing machine is Micheal (played by Paul Bettany). He goes to earth in defiance of the mission God sent him to carry out. Although it makes no sense at all, God reverts back to his vengeful version to smite humankind and Micheal is not cool with than. Michael then travels to a diner in the middle of the desert to protect humankind's last hope: a child to be born from an unwed waitress. The parallels to the Nativity Story are there, but with in an apocalyptic backdrop.
I have to be honest in saying that while the action is there and film has suspenseful moments, the premise of the movie just doesn't fly with me (God sending angels to possess people to hunt down the savior child). Plus, there are just things that don't add up, like who decides which people are going to be possessed and why some angels opt not to possess people. BTW, the possessed people are very much like zombies.
Legion will leave you wanting more because the weak premise is stretched enough to make it marginally enjoyable. I'm definitely not a part of the legion of fans of this film.