So, I'm somewhat familiar with the Fletch movies from the 80s starring Chevy Chase, which I saw before discovering the movies are based on a series of books and OfCourse like most book adaptions, those movies are not true to the source material (what a shocker)

Not sure if this new one starring Jon Hamm is true to the source material or marketed to be. What I saw was not that different from the Chevy Chase films. The big exception was while Hamm's Erwin Flecther used a bunch of fake names to investigate a murder, he's being accused of doing, by a cop brilliantly played by comedian Roy Wood Jr. Who natural looks like the Roger Murtaugh type, Chase's Fletch went a step further by becoming the names he made up as somewhat of a master of disguise in a series of segments in the movie that could pass as Saturday Night Live sketches.

With all that said i can't say either versions are better or worse than the other. All I can say is that both versions are great in their own right, but if you enjoyed the Chevy Chase version, you'll love the Jon Hamm version (unless you are not a fan of the Mad Men star). They both seem to do a good job at making Fletch charming.