Someone mentioned being inspired to read the books. Good.
Read them in the order published, or in no order at all.
The back story is introduced a little at a time, both as Child develops Reacher, and as we get to know the character. Same way we learn about our acquaintances. We don't know them chronologically, since even childhood friends are not with us at all times, we learn bits and pieces about them.
After the softcover story "The Affair" is a short story of Reacher when he was a kid. That was one of the best Reacher stories I ever read.
Child is a Brit, living in the US, and seems to have gotten a good grasp of his Army terms, American life, life on the road, human nature, etc. Some of his recurrent characters are pretty strong, even if some of his situations are a bit of a stretch.
Never mentioned in the narratives, but I think Reacher has a bit of a mental health problem, to wit PTSD. He distrusts authority (usually with good cause) travels incessantly and doesn't own anything if he can avoid it. He is dealing with getting screwed by the Army, and several losses. However, Child deals with this realistically, since his character is reasoned, considers all the factors, and is clearly (to the reader) not a loose cannon, regardless of his coiled spring setting. He has a couple of idiosyncrasies, That don't get introduced (chronologically) until later, and it is fun to watch the writer play with those. There is also a ending to one of the stories that caused a great deal of controversy, since so many don't think Child dealt with it in the beginning of of the next story adequately. You'll know it when you see it.
As to the actor choice, I am sure Cruise brought a bunch of money into the early negotiations, and said basically, "I'm the star." If someone like the Rock, had more gravitas, and was a bigger wheel in Hollywood, he might have made a better Reacher. The role requires someone with a smoldering heat, and Cruise telling someone he better walk away, just doesn't carry the threat of Reacher doing it.
