WATCH: 'On the Road' Official Trailer

Maybe it's been years since you read Jack Kerouac's On the Road (or you never read and only pretend to when someone mentions it). But you should know that there's lots of sex and drugs and jazz and more in the book. And it just so happens, it's in the movie that comes out December 21 (including Kristen Stewart giving two men handjobs in the front seat of their car).

Even if you don't cop to this twenties exploratory romp in 1940s America, you'll never forget Garrett Hedlund after seeing him in the film. And here, in the official trailer, you get a lot more Hedlund action, who plays Dean Moriarty, and is the central catalyst for the book and film.

Oh, one caveat: if you're looking for a family friendly holiday flick, this isn't it. Unless you and your family don't mind watching lots of nudity together. Check it out below: