If you like the movie, you'll love the books more

Rating: 6/10 (1 June 2020)

One of the challenges to adapting a book to a screenplay is that the action descriptions in the book allow detailing how 1 guy can take down 5 others in a street fight. When filmed, the fight may take place in 30 seconds and hits take a half second. In the book, the fight techniques are described in pages of detail.
Another challenge is that although the Jack Reacher books are fun, the villains can be a bit James Bond cartoonish. On screen, "The Zec" appeared forgettable. We ignore this in the book because Reacher's experience is what where the excitement is, but on screen, the script writers should have developed that character more. I cared more for when horny teenagers were knocked off in Friday the 13th than I did for these villains.
Next, the chase sequences in the film were more Mission Impossible than the undercover-vagabond that Jack Reacher is. Tom Cruise is known to be a great car driver, but Jack Reacher rarely gets behind the wheel. The charm of Jack Reacher was lost as the film merged with other Tom Cruise, er, vehicles.
Which leads us to something others have said here: Casting Cruise as Reacher. Reacher's attractiveness to the ladies stems not from James Bond style and charm, but rather raw muscle and height with him being smarter than he looks.
Now that's all the bad news first. The good news is that much of the philosophy of Reacher and his way of thinking was represented in the film, albeit subdued by the action sequences. The story was reasonably well represented. What makes a Reacher novel fun to read is following along with Reacher's mind as he solves the mystery so some of that would be lost in trying to read this novel after seeing the film. But (most) other Reacher novels are of similar quality or better than the source material for this film. So use this film as a gateway to the Jack Reacher universe.