Seeing “Nymphomaniac Vol. II” a couple of weeks after the release of the first half of the film is more than just a case of cinema interruptus. It proves how much the opus needs to be seen as a single picture, preferably in one go.

So intriguing in its first couple of hours, “Nymphomaniac” scrambles to get back into gear as “Vol. II” resumes the story; more nagging still is the feeling that while the material darkens, it doesn’t necessarily deepen.

We return to the room where Joe, a no-longer-young sex addict — though she prefers the term nymphomaniac — is recounting her life story to the intellectual Seligman (Stellan Skarsgard). Joe continues her journey through a variety of partners, willing to lose husband (Shia LaBeouf) and child in order to be on time for her abusive appointments with a whip-cracking sadist (Jamie Bell).

Joe is once again played as a young woman by Stacy Martin, though Charlotte Gainsbourg takes over the lion’s share of the flashbacks before too much time has passed.

Writer-director Lars von Trier appears to be making a movie about female sexuality — but maybe not. I wonder whether this half of the film suggests more strongly that “Nymphomaniac” is really about everybody else in Joe’s life, all the people who must grapple with her brazenly stated appetite for sex.

From the enigmatic Seligman (the film’s real suspense is how the present-day segment will end) all the way down to the hapless translator who facilitates a bilingual liaison, the ranks are filled with people who can’t handle her ongoing search. And the movie viewer, having been drawn toward this mostly non-erotic movie full of nudity and brutal sexual violence, is implicated in that circle as well.

It’s hard to settle on von Trier’s purpose, although he baldly offers many possible readings, from the desperate need for people to fill the void of existence to the idea that power and pleasure might be gained by ceasing to strain against one’s chains.

Any conclusions are complicated by reports that von Trier’s cut of the entire “Nymphomaniac” opus is an hour longer than this one, which might explain why the final chapter — involving Joe’s curious work as a bill collector for gangster Willem Dafoe — seems under-dramatized.

One thing would presumably remain the same in a longer movie: the bleakness of the fade-out. The filmmaker’s view of humankind has not sweetened in the course of this journey, and we shouldn’t be shocked if von Trier leaves us literally in the dark.

“Nymphomaniac Vol. II” (three stars)

The second part of Lars von Trier’s episodic look at a woman (Charlotte Gainsbourg) recounting her dangerous sex life to a stranger (Stellan Skarsgard). The saga darkens here (there is much brutal violence) but doesn’t necessarily deepen in this part, although von Trier raises intriguing questions about the way the rest of the world regards brazen female sexuality.

Rating: Not rated; probably NC-17 for nudity, violence, subject matter

Opening: Friday at Guild 45th and Thorton Place Stadium.