In Lee Child's series of books, former Army Military Police Major Jack Reacher is a huge imposing man whose 6'5" shadow engulfs everyone around him. So when it was announced that Tom Cruise (who stands at only 5'7") would portray the character onscreen, there was a little (heh) concern.
Reacher is a highly-skilled fighter and investigator who's only interested in seeking out the truth no matter where it takes him. So Cruise may not fit the physical attributes of the fictional drifter in Jack Reacher, but he does capture the essence of the character very well.
Reacher’s lack of remorse for any of his actions allows him to push headstrong into any situation – almost always coming out on top.