Call it a 3.5. Reynolds offers a reading of the superhero from its inception with Action Comics to the current (1990s) day, suggesting that it may have run its course, in comic form at least. The book is somewhere between a scholarly text and nonfiction; there's some very close readings, but it's all very readable. And yet, the whole thing would I think be much improved if Reynolds lifted the curtain a bit or showed his hand earlier (mixed metaphors!) as to what end he is constructing this argument.
The first chapter covers the basics of the genre, offering a history of superheroes and using Action Comics #1, the first appearance of Superman, to establish the seven major traits that he argues define the genre, including societal isolation marked by a lack of connection to parents; earthbound gods whose powers vary with how well they get along with regular people; devotion to justice over the law; contrast between superhero and normal person, and their alter ego.; some loyalty to the state; and mythical stories that combine science and magic. (It makes interesting mappings onto Coogan's typical mission identity power definition.) The point is solidified by going through a Batman story demonstrating these seven ideals.
The second chapter starts at costume and ends at continuity. A discussion of how costume reflects identity takes a slight digression to look at the fetishization of the female form, then ends a bit abruptly with the notion that costumes create a community. That shifts things to intertextuality and continuity--serial continuity which is the ongoing story; hierarchical continuity, that we have power levels implied and a focus on fighting; and structural continuity, that at any given time, you have a system that describes a larger superhero universe. (He employs some Saussurean terms in the chapter to solidify the discussion.) That allows us to believe in superheroes as myth, establish the fan and creator relation. The chapter ends with an interesting argument that on the individual issue level, the villains are the protagonists for shaking things up, but on the larger mythic level, the heroes take that role.
The rest of the book is essentially case studies, with one chapter on superheroes that fit this mythic parameter, and and other on books that break it. First, we have Thor, whom Reynolds argues is interesting for the way he's made the transition from ancient myth to comic book form. (I agree with this, though there are some other interesting character that work in this direction too, from Moon Knight to Wonder Woman.) He reads Superman in Oedpial terms, and Batman in terms of his villains and the price he pays for being Batman. The chapter concludes with the idea that superheroes work to preserve the status quo, and he offers some examples of failures to engage with social issues as a result, and illusions that make it look differently.
The final chapter looks at Claremont and Byrne's initial X-Men run, Dark Knight Returns, and Watchmen. The tie between the last two texts is pretty clear, but the X-Men may seem like odd men out. I think what Reynolds is going for here is the idea that the X-Men, at this stage, represent the pinnacle of the superhero genre, the most you can get out of them as myth, through their combination of individual and collective action. The Dark Knight Returns and Watchmen, on the other hand, is the superhero being deconstructed and collapsing. This line of thought continues into the epilogue, where he looks deeper into where the industry is now in terms of being either ultraviolent superheroes, or new creators creating new things, using the death of superman and the subsequent four new supermen as the metaphor for that moment.
It's an interesting argument--and even maybe a right one, given that while superhero comics have gone on, it's clearly other media that are driving now--but the book does tend to meander a lot. It could use a bit more staying on task, and a bit more of an explicit frame to keep that task in the reader's mind. That said, some of the digressions are fascinating; I'd like to see a much more in-depth discussion of what he has to say concerning the superhero's fetishization of women and simultaneous denial of that fetishization. And as an early bit of comics scholarship, it captures history and trends in superheroes pretty well, and better than later books in some cases. (It's also a quick read, but an expensive read--the paperback goes for $100 now. Yikes.)