Last spring, the inimitable Siân reviewed Insurgent, the second movie in the Divergent series. Among her observations: “Things exploded. A lot.”

I doubt it will surprise anyone that in Allegiant (directed by Robert Schwentke; Summit, March 2016; PG-13), the third adaptation in the trilogy — no, wait, the first part of the two-part adaptation of the third book in the trilogy — more things explode.

That probably doesn’t count as a spoiler, but it’s almost impossible to say more about this movie without some spoilers for the series as a whole. I’ll try to keep the spoilers for this installment, at least, as vague as possible.

The conclusions, two-part or otherwise, of dystopian or post-apocalyptic stories often find themselves in an odd position. Divergent, like many series-starters in the genre, kept readers turning pages and moviegoers sitting on the edge of their seats by raising questions. What’s the purpose of the city’s factions? What really happened to District 13? What’s beyond the city wall? Insurgent, for all its flaws, had a perfect cliffhanger ending: it was finally time to answer that last question, and probably some related questions along with it. Allegiant’s job, then, is to provide answers and hope they’re as satisfying as the mysteries were tantalizing.

To the books’ credit, the answers are original; they build on issues from our world, but they’re the Divergent universe’s own (occasional logical holes and all). But the book does a better, more thorough job than the movie of explaining how humanity got from point A (our present) to point B (Tris and co.’s future). The movie has more cinematic priorities, like getting to the parts where no one trusts anyone else and everything’s hi-tech and shiny. (And sometimes hi-tech and goofy. Did you know that in the future, you can be decontaminated by goop reminiscent of Nickelodeon slime that will make you make weird screamy-faces? Neither did I.)

A lot happens in Allegiant, the book. Not all of it happens in Allegiant, part one of the movie. But a story arc does happen, including events from both halves of the novel. I’m not sure what’s left for Ascendant, the conclusion of the conclusion, other than one key event that those who’ve read the book can probably surmise. Of course, they’ll have to sort-of-explain all that backstory all over again, so there’s that.

The cast does a valiant job, from the always-likable Shailene Woodley as Tris to the hilariously smug Miles Teller as Peter. Octavia Spencer is pissed off but poised as Johanna, the former head of the peaceful Amity faction who’s reached the end of her patience. Ansel Elgort is appropriately doofy as Caleb, an intellectual from the Erudite faction who suddenly has to do dangerous things he’s only read about. Jeff Daniels as David is as patronizing as David should be when he’s telling Tris...but now we’re verging on too spoilery. Let’s just say he’s patronizing whenever he tells Tris anything.

Allegiant is a chance to revisit the characters who are left standing and watch them deal with situations completely new to them. The book has some big reveals that shed major light on the previous installments; the movie has not-quite-as-clear versions of the same revelations. The movie manages to structure about half the events of the book so that there’s excitement, adventure, and, as I said above, a story arc. It just could’ve been a drop longer and completed that story.

But then the box office numbers for the franchise wouldn’t be quite so Ascendant.