There are quite a few ways to continue a series after you've reasonably concluded it – twice. Reki Kawahara appears to be using two of them: go back and expand on what you've already written (the SAO: Progressive novels) and add in a new character who is much more interesting than your current protagonist and have her take up many more pages in the book than the nominal hero. That latter is what makes Sword Art Online's fifth novel, subtitled Phantom Bullet, a better read than its predecessors in the ALO story arc. While there technically isn't anything wrong with having an overpowered hero (children's and young adult fiction in the nineteenth century did it all the time), it is very old-fashioned, and today's readers often prefer their protagonists to have some flaws, serious or otherwise. This has made Kawahara's Kazuto Kirigaya, also known as Kirito, a bit difficult to stomach at times, with his seemingly perfect grasp of just about everything and apparent irresistibility to women. While Kirito is still very much present in Phantom Bullet, he gets far less page time than in previous books (even the Fairy Dance novels, which featured his sister Suguha quite a bit, still were predominantly his story), and Kawahara also begins to explore his potential weaknesses more, making this feel like the most contemporary (in terms of style) of the series thus far.

The novel opens inside a VRMMORPG that we as readers have never seen before: Gun Gale Online, or GGO for short. GGO is an American-produced cross between an MMO and a first person shooter (FPS), where players fight each other in a post-apocalyptic world armed with a mix of fantasy and realistic guns. One player, a man calling himself Death Gun, seems to have found a way to circumvent the system similarly to Kayaba back in the first book: if he shoots someone in the game, they die in real life. He's only taken down two players so far, but since no one appears to be paying attention, he has plans to take out many more. What he doesn't know is that the notoriety he craves is already happening: the government, wary after the SAO incident, has begun to get nervous, and they call in Kirito to help. Kirito is (understandably) reluctant to leave ALO and check out this new game: he's got his girlfriend back, he has friends, and generally appears to be leading a normal life. His bespectacled government contact isn't taking no for an answer, though, and before the first chapter ends, Kirito finds himself agreeing to check things out.

And then we don't see him for another sixty-eight pages.

While Kirito might be the savior figure of the story, most of this book (if we go by chapter count, and possibly pages as well) belongs to Shino Asada, called Sinon in GGO. From the start she's a much more interesting character. While she is easily just as talented a player as Kirito or Asuna, there's much more going on interiorly than with either of them. Shino is suffering from a childhood trauma that's truly horrific, one for which she has been ostracized from her peer group and even her hometown. Moving to Tokyo for a fresh start in high school, she quickly becomes the victim of a group of bullies, who spread her history around when they don't get their way. Unable to open up to therapists, Shino is prone to panic attacks and all the other horrors that come with PTSD, and somewhere in her mind she yearns to go from being a victim to a survivor. Since her past trauma involves firearms, she accepts a friend's invitation to join GGO, where she quickly crafts a (she perceives) stronger, tougher version of herself in Sinon as a means to help her to overcome her problems.

What makes Sinon a more successful character than any to previously appear in the main series is that she has more depth. Rather than being just a scared or traumatized character, she's someone who is actively working to change herself. We could argue that Kirito and Asuna also do this in the Aincrad arc, but since that shows up so much better in SAO: Progressive, it feels like this is a turning point for Kawahara's writing skill. Sinon isn't perfectly depicted, but she's got more going on than previous characters...and not a little like a better-written Haruyuki from Kawahara's other similar series Accel World.

Speaking of Accel World, it is becoming increasingly clear that it is the future of SAO's world, and Kawahara is getting decidedly less subtle about that. This may be a more smoothly written book with a more interesting protagonist, but it's still clunky in its exposition and attempts to be sly, such as the several ways he tries not to say that Kirito's new weapon looks like a Star Wars lightsaber. Asuna's small role in the book also returns to Kawahara's difficulty in writing believable women, making it interesting that Shino mostly escapes this trap.

Perhaps part of the appeal of this novel is not just the characters, but also the fact that GGO is so different from the games previously explored. People who aren't fans of guns may find that the descriptions don't tell quite as much as they ought, or may simply dislike reading so much about gun-based violence, game or not, but the change to an FPS really does help to rejuvenate the series. Shino's character allows Kawahara to spend some time looking into the psychological effects of both Aincrad and Fairy Dance on Kirito, which was definitely overdue, and all in all this entry into the series really feels as if it is opening things up to be a more thoughtful, or at least better thought out, continuation from here on out.