Given scene/plot descriptions from movies or TV shows, and given a specific question about the scene, summarize the question into a title

Having seen Jack Reacher, and not having read any of the Lee Child books upon which the film was based, I was surprised by the amount of humor in the film. These elements reached their nadir with a bizarrely slapstick scene involving an attempted murder with a baseball bat in a bathroom. I know a little about the books and character, and was surprised by the inclusion of a scene like this (plus other comedic asides). Is this tone true to the book series, or did Christopher McQuarrie deliberately change things up through his script and direction?
Are the comedic elements in the film Jack Reacher evident in the novels on which it was based?