Tom Cruise has been having some kind of rollercoaster week. After the shocking announcement of his divorce from Katie Holmes -- just before his birthday, no less -- Paramount Pictures chose to release a new trailer for Cruise's new action film, Jack Reacher, on the actor's 50th birthday. The trailer is currently available on Yahoo Trailers, and it is also embedded at the bottom of this page.

Jack Reacher, which went by the working title One Shot, has the Mission Impossible star stepping into the big leather boots of Jack Reacher, the famed vigilante dreamed up by British author Lee Child.

At the beginning of a trailer, we see a heavily bandaged man lying in a hospital bed.

There's this guy, he mutters. He's kinda cop, at least he used to be. He doesn't care about proof. He doesn't care about the law. He only cares about what's right. And guess what I did. ... You can't protect me. No one can.

In the background, we see a few scenes setting up Reacher's character. He's bold, he's tough, and he's got a sweet car. The minutes-long teaser doesn't include many juicy scenes, but it does show off Reacher's famous car. Even though this is a Nova SS, not Reacher's beloved 1970 Chevelle SS, it still roars and sings all at once.

You think I'm a hero? Cruise's Reacher asks. I am not a hero. And if you're smart, that scares you, because I have nothing to lose.

In the trailer, Reacher then proceeds to kick a lot of butt.

Jack Reacher: The Books Vs. The Movie

Cruise may have the star power to back a role like Jack Reacher, but at 5-foot-7, he doesn't seem quite as intimidating as the literary character. From Wikipedia:

Reacher is a giant, standing at 6' 5 tall (1.96m) with a 50-inch chest, and weighing between 210 and 250 pounds. He has ice-blue eyes and dirty blond hair. He has very little body fat, and his muscular physique is completely natural. He is exceptionally strong but is not a good runner. Reacher is strong enough to break a man's neck with one hand and kill a villain with a single punch to the head or chest. In a fight against a 7 foot, 400 lb steroid-using thug [in Persuader], Reacher was able to lift his opponent into the air and drop him on his head.

I'm not sure Cruise will be able to lift the film's romantic lead above his head, much less a 7-foot, 400-pound assassin. Regardless, Lee Child himself commented on these differences:

It's completely impossible to literally transfer the page to the screen, Child told the BBC. Ironically, to capture the feel of a book on the screen, you have to change almost everything about it. People think we should have had an actor that looks more like Reacher is described in the books. First of all, there aren't any such actors, so it's much more a question of which actor has the talent and screen presence to create what Reacher does on the screen, and that really comes down to finding the actor with the most talent.

Child added that he was thrilled Cruise had accepted the role.

The Jack Reacher trailer also reveals a few differences in the general character background. In the movie, the wounded man on the hospital bed describes Cruise primarily as a cop; we don't get anything about his military background. In the books, Jack Reacher is a highly decorated U.S. Army miltary police veteran who quits to become a drifter. Again, from Wikipedia:

He wanders throughout the United States because he felt he never got to know his own country, having spent his youth living overseas on military bases. He usually travels by hitchhiking or bus. As a drifter, the only possessions he carries are money, a foldable toothbrush and, after 9/11, an expired passport. He wears his clothing for 2-3 days before discarding it, usually purchasing new clothing cheaply from chain outlets. He has no steady income and lives on savings in his bank account and part-time jobs. At various points during the series, his bank account is supplemented by taking money from his enemies. Reacher knows how to drive although he is admittedly not a very good driver. He has never possessed a driver's license.

Besides these facts, we currently know very little about the movie, but more parallels between the books and the film will surely surface as we get closer to the film's release in December.

Jack Reacher was directed by Christopher McQuarrie, who previously worked with Cruise on the 2008 World War II film Valkyrie. The film also stars Robert Duvall, Richard Jenkins, Rosamund Pike and German director Werner Herzog. Watch the film's trailer below and feel free to leave us your thoughts and impressions in the comments section.