The first arc has the basics, but not much else.
If a chain is only as strong as its weakest link, then a story is only as strong as its biggest flaw. Every story has to skip a few details. Sometimes it's necessary to ensure a concise, coherent narrative. As Ash found out at the end of Evil Dead 2, however, a casual oversight can have serious consequences. It doesn't always involve invading demon hordes, but in the case of Extraordinary X-men, it can lead to evil clone monsters. As Spider-Man can attest, evil clones rarely pan out well.
When Marvel opted to do an eight month time-skip after Secret Wars, a few details were bound to get lost in the mix. Details like Jessica Drew getting knocked up and Kamala Khan joining the Avengers offered more intrigue than confusion, but there's a fine line between genuine intrigue and chorus of "Huh?!" In Extraordinary X-men, nobody even tried walking that line. Marvel did the swan dive over that line and into the deep end of a pool of hungry sharks.
From the final issue of Brian Michael Bendis' run in Uncanny X-men #600 to the first issue of Jeff Lemire's run in Extraordinary X-men #1, the shift in tone is akin to watching Saving Private Ryan after watching Happy Gilmore. It's not just that mutants are in a new state of turmoil; it's that the journey into this turmoil happened off-panel.
For the first four issues, only a handful of clues have been offered, most of which involve Cyclops becoming the most despised person associated with the X-men since Chuck Austin. The limited scope of these clues have hindered the Lemire's narrative, but have still offered points of intrigue. The narrative here is still developing. It's just trying to develop with one hand tied behind its back and suffering a broken ankle and a severe concussion.
Extraordinary X-men #5 is intended to solidify this new foundation for the X-men. It has successfully, albeit messily, brought all the necessary characters into the right place. It's still building on top of a foundation with some major cracks in it, however. By the end of the story, those cracks don't get any smaller. That building still wouldn't pass an inspection without a hefty bribe. At the very least, however, it's coherent and it doesn't create any new cracks.
The conflict here is basic X-men 101. Sinister has unleashed a monster by mixing mutant and Inhuman DNA. That monster threatens humans and mutants alike. The X-men come together and stop it. It's every bit as basic as Captain America punching the Red Skull in the face. There's nothing novel of innovative about it. But for the first arc in this series, that's entirely appropriate.
It at least tries to come off as something more dramatic. It actually teased the possibility that some of the gaping plot holes in this narrative would be filled in, revealing that Sinister's monster may or may not be Cyclops. But in the same way that sending money to a Nigerian prince via the Internet rarely pays off, this effort yielded nothing. Like seeing the promiscuous teenager die first in a slasher movie, it surprised no one when this monster just turned out to be a clone.
There was no dramatic weight whatsoever. There was painfully little context. Sinister claims he's trying to help save the mutant race and improve it. For some reason, he still thinks clones are a good idea this time. He's like someone who refuses to upgrade from VHS tapes. It's hard to really take him seriously. His charisma and cunning, which helped make him one of the X-men's most devious villains, just wasn't there.
If there is a sliver of drama in this story, it comes from Storm. This fight against another Sinister-bred clone gives Storm the chance to establish herself as the new leader of the X-men, and she does this to great effect. She's able to coordinate with her teammates to take down the monster. She also emphasizes protecting the same humans that hate mutants now more than ever. This isn't just appropriate for the X-men. It's required. Storm is able to check all the boxes that Halle Berry couldn't in X3.
Under Storm's leadership, the X-men effectively establish that they're not going to curl up in a fetal position and led an Inhuman dominated world kick them into submission. They're still going to be X-men. That's all well and good. But once again, the lack of a context completely robs this moment of any drama. It's like watching only the last two episodes of Breaking Bad. Without knowing the details of the story that led up to this, it's impossible to appreciate the breadth of the story.
When Extraordinary X-men began, it teased that something had gone horribly wrong during the eight-month gap between mutants and Inhumans. We know nothing about this conflict. We only know that at some point, Cyclops got himself killed and somehow managed to become the most hated non-clone mutant of all time. It's conveyed as a mystery, but it basically comes off as the kind of trolling that is best restricted to Walking Dead message boards.
This isn't like the aftermath of Avengers vs. X-men or House of M. These conflicts all happened on-panel and as part of major events. This phantom war with the Inhumans happened entirely off-panel and the story forces readers to assume that Cyclops just did something so horrible that he would've been better off just driving a truck of puppies off a cliff. It tries to be a mystery, but in Extraordinary X-men #5 it just comes off as an excuse to circumvent the major flaws in the narrative.
Absent an understanding of the conflict that created this situation, Storm's speech that the X-men were back basically amounts to scapegoating. That's exactly the kind of thing the X-men are supposed to oppose. Her speech might have rallied the team, but it has less depth than a commercial for car insurance.
Extraordinary X-men #5 succeeds in the basics, but not much else. The inherent flaws in the narrative render it impotent in terms of having an impact. However, these flaws don't completely undermine the potential of the story. There's still time to fill in these gaping plot holes to help give weight and context to this series. But like watching Tom Brady in a two-minute drill, it feels like that time is passing faster than it should.