Swan Song review: Mahershala Ali is his own costar in a sci-fi tone poem too heavy on mood

Whatever the brand of future-panic in most science fiction — scarce resources, soulless technology, rising robot overlords — what's at the root, usually, is our own obsolescence. Beneath its sleek veneer of android baristas and bullet trains, Swan Song (out today on Apple TV+) is no exception, even if it's unclear for most of it whether the film means to frame that as a comfort or a cautionary tale.

Writer-director Benjamin Cleary does eventually choose, though his moody tone-poem of a debut finds its strongest focus in the twinned performance at its center: Two-time Oscar winner Mahershala Ali, who stars as both an ailing man named Cameron Turner and his AI replacement, "Jack." Cameron is dying, but if two scientists (Glenn Close and Adam Beach) can successfully clone him, his wife Poppy (Naomie Harris, reunited with her Moonlight costar) and young son (Dax Rey) will never have to know.

The physical match is flawless, but that may be cold comfort: For all her calm assurances and lovely accommodations — the lab where this "substitution" will take place seems to be located on some kind of glittering fjord — Close's Dr. Scott finds a reluctant client in Cameron. How can he trust this blank slate who wears his face to be the father and partner he desperately wants to be but won't survive to see? As the narrative cuts back and forth in time, it shows how his and Poppy's romance came to be (there's a meet-cute on a commute), and what exactly it is he'll be losing when he goes.

There are a lot of lovely, artfully framed montage memories in that, and some real humor and pathos in Awkwafina's supporting turn as a fellow patient who has already crossed the Rubicon that Cameron's still considering. But for all the impeccable set design and Black Mirror timeliness of the storyline, Swan largely sidesteps the tricky ethical questions it raises. Instead, the movie lets them float away and dissipate, settling for a sort of simmering low-key dreaminess that even Ali's poignant performance(s) can't quite pierce. Without much dramatic tension beyond the will-he-or-won't-he of Cameron's final choice, the film feels oddly inert, a melancholic iPhone ad stretched to feature-length. Grade: B–

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