In the particle physics community, the past 20 years has been filled with either very exciting new discoveries, or a complete lack of progress, depending on your point of view. The reason for this is that the majority of research in this field of science has been devoted to a theory which some don't even view as proper science.
This theory, which has excited many and dumbfounded even more, is known as String Theory, Super String Theory, or M-Theory, depending on the version you are studying. Not Even Wrong attempts to make the unpopular case that string theory, and its more recent derivatives, is failed science and should be abandoned so that scarce resources can be devoted to other more promising theories.
The idea that a theory can not only be wrong, but "isn't even wrong" was popularized by the physicist Wolfgang Pauli, to describe that an idea that isn't just wrong, it doesn't actually make any predictions which are either verifiable, or falsifiable, and thus provides nothing of value. To some brave physicists who are willing to espouse such views, string theory would seem to fall into this category.
This book is definitely not for the faint of heart in terms of communicating complicated math and physics. I had to read through the first half of the book twice in order to get a decent understanding of the ideas being thrown out. Much of this first half is a history lesson of theoretical particle physics, but with some technical elements easy to get lost in. It describes in some detail the major breakthroughs that occurred pre- and post-WWII that culminated in the development of the Standard Model, and different versions of quantum theory.
Sometimes this history lesson is nothing more than a listing of important events, without much context as to why it's important to the central theme of the book. After finishing the entire text, it is now obvious that the entire point of the first half of the book was to layout the case (a case which many would say should need no explanation) that physics should be based on experimentally proved facts, and not on hopes and grand ideas that can't be proved. This laundry list of experimental evidence is left in stark contrast the lack of evidence that string theory has to back it up.