What do Joyce’s “Ulysses,” Tajikistan, night terrors, Bob Dylan, fraught fatherly relationships, Russian spies, astrophysics, Jacques Lacan, dependent disabled brothers and Jackson Pollock have in common? In the unlikely infinite-monkeys-infinite-typewriters scenario whereby this becomes an actual riddle, you now have an answer: nothing, but they all pop up in Arnaud Desplechin‘s “Ismaël’s Ghosts.” If storylines were measured in yardage, laid end to end the film’s narratives could comfortably lasso the moon, but its very fundamental problem is that they’re not laid end-to-end. Nor are they tangled up: the temptation is to call it “labyrinthine,” but that would misunderstand the nature of labyrinths. Instead all the film’s many disparate story strands unfold in parallel, never touching, never crossing, never illuminating each other. When in this sort of doubt, the Critics’ Handbook suggests one should just summarize the plot. But who wants to read a 14,000 word review?

There’s a plethora of plotlines and no discernible overarching theme (perhaps there’s no room), but there is, however, a central character and for the sake of our sanity, let’s start there. The eponymous Ismaël (Mathieu Amalric) is a filmmaker, which means we get to read him as an analog for Desplechin himself, not that that leads us anywhere particularly interesting. Across the two time periods in which the film elapses, he’s been the bereft husband of the disappeared-and-presumed-dead Carlotta (Marion Cotillard) for around two decades. He has put his life back together, however, thanks to astrophysicist Sylvia (Charlotte Gainsbourg) and we know this because they have frequent wordily declarative conversations about how she saved his life. Ismaël and Sylvia are vacationing at a beach house when Carlotta suddenly strolls up out of nowhere and re-insinuates herself into Ismaël’s life. For a short while Carlotta, apparently destitute and ethereally unapologetic about her 20-year disappearance (and interim marriage in India) shacks up in the spare room and the three co-exist uncomfortably.

It’s a testament to the commitment of all three actors that this aspect of the film is actually fairly engaging. They all manage to find a certain truthfulness in their high-drama situation, despite mercilessly self-analytical dialogue such as, “I’m leaving. I don’t know how to love myself enough to ask you to come with me” — you have to keep careful track of the personal pronouns. But actually this basic love triangle would have been entirely enough to power the film. Gainsbourg has the thankless task of playing the earthbound version of Cotillard’s trademark melancholy mystery-woman, but the way it all shakes out feels vaguely like it’s the long-game comeuppance of a Manic Pixie Dream Girl, and that’s its own sort of satisfaction. The “lifesaving” Sylvia tearfully exclaims, “I wanted to drive you crazy, not make you reasonable” to Ismaël, but the film gently comes down on the side of the partner who provides the grounded, stable support, not the swoonsome amour fou.

But there’s so much else going on here, it’s hard to even call this the heart of the story. Co-screenwriters Desplechin, Julie Peyr and Léa Mysius (only three of them? It feels like more) let the strands multiply like rabbits, with a whole ongoing section being a film-within-the-film, the one Ismaël is shooting. Apparently, it’s a spy thriller loosely based on the life of his actual brother, and scenes are presented like they’re part of the main narrative to endlessly jarring effect. Here Louis Garrel plays Ivan Dedalus (and Ismael’s father-in-law’s name is Bloom, hence a Joyce allusion because, sure, why not) and Alba Rohrwacher plays his wife. There’s a whole Greek chorus of fellow spies who talk about Dedalus like he’s some sort of mythic figure, and fun bit where someone gets his head blown off by an exploding phone.

Back in the real world, Carlotta’s aging, heartbroken father (Laszlo Szabo), Ismael’s persistent long-time line producer Zwy (Hippolyte Girardot), and the tentative start of Sylvia and Ismael’s romance all get their own long discursive segments, and the narrative multiplicity feels even more frenzied because of Desplechin’s kitchen-sink filmmaking. He throws rapid zooms, back projections, partial dissolves, direct addresses, herky jerk, borderline pastiche scoring and occasional voiceover at the wall to see what sticks. The zany confidence of the approach is admirable, but what starts off as exuberance starts to wear thin when it becomes increasingly clear that none of these techniques is deployed with any kind of thematic logic. Pretty soon you start waiting for the film, not to end — that already feels optimistic — but simply to stop.

Desplechin is a prolific but uneven filmmaker: his last Cannes title, “My Golden Days,” was a delight; his previous feature, “Jimmy P.: Psychotherapy of a Plains Indian,” was a meandering indulgence. “Ismael’s Ghosts” is a curiously in-the-moment watchable amalgam of all his best and worst tendencies: a film of so many different personalities it feels like several different films inexplicably spliced together. As fun as some of those films are, embellished with lunatic moments like Cotillard’s coolly bizarre dance to Bob Dylan’s “It Ain’t Me Babe” and a whole random bit with an attic and some paintings and a gun, nothing coheres. Desplechin lashes storylines and filmmaking gimmickry in to the one ginormous stewpot with gusto, slams the lid down on it and promptly forgets to turn on the heat. Two hours later, you’ve got a pot full of raw ingredients and nothing to feed the family. In the same way you emerge after “Ismael’s Ghosts” noticeably the same as when you went in, just two hours older, and starting to go a little brown around the edges. [C+]

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