Renee Zellweger goes over the rainbow in Judy Garland biopic Judy

Sometimes a movie is so much about the performance at its center that it almost feels irrelevant to talk about plot or setting or supporting characters — anything but the actor around whose centrifugal force the story orbits like a small, not especially significant planet around the sun.

Renee Zellweger does that in the Judy Garland biopic Judy, disappearing so completely inside the skin of her iconic subject that it feels less like role-playing than a sort of full-body possession, or a summoning. The framework of the story itself is modest: it all takes place, aside from a few heavily expositioned flashbacks, over a few months in the twilight of the singer-actress’s career.

As the movie opens, Garland is in her mid-40s — still known, but hardly on top anymore. She’s hoofing it for whatever meager bookings she can get, sometimes with her young son and daughter accompanying her on stage; technically, though, she’s homeless. Her ex-husband (Rufus Sewell) doesn’t want to put her up and she seems to have run all out of fallbacks and favors in Hollywood, so an offer for a series of shows in London sounds like a lifeline, even if it means a painful separation from her children.

If the blond, marathon-lean Zellweger hardly seems like a natural doppelganger for Garland, she still manages to subsume herself entirely in the role without ever tipping over into some kind of gestural Judy drag. With her heavily lined koala-bear eyes and inky quiff of hair, she finds her subject physically, but what most invokes the famously troubled star is the mix of supreme stubbornness and tender-hearted vulnerability she projects in nearly every scene.

Arriving in London, Judy is both combative — she refuses to rehearse, and practically has to be poured into a dress and dragged on stage opening night — and privately anguished, racked with insomnia and desperately missing her kids. The surprise arrival of a much-younger man she met just once at a party in Los Angeles, a shiny-bright pile of sideburns and dimples named Mickey Deans (Finn Wittrock) helps bring her back to life. But even his stabilizing presence, and the diligence of her infinitely patient young minder, Rosalyn (Chernobyl’s Jessie Buckley), can’t keep her in line for long.

Director Rupert Goold (True Story) chooses to frame his story in a handful of callbacks to Garland’s early days at MGM, with a Weinstein-esque Louis B. Mayer as the big bad wolf who ruthlessly berates his teenage star (she’s ugly, she’s fat-ankled, a thousand girls could take her place), and a scowling chaperone who grimly feeds her uppers to suppress her appetite and downers to knock her out (the consequences, unsurprisingly, lasted the rest of her short life).

It’s clumsily effective in showing why Garland grew up with a hole she spent decades filling with pills and husbands — altogether, there were five — but it feels unnecessary, too. The best scenes in Judy are the small ones that happen off the stage, especially one sweet sequence in which she spontaneously spends an evening with two awestruck fans, and the big ones on it, belting out the songs that stopped men like Mayer in their tracks.

About those musical numbers: That’s Zellweger’s singing alone, which might seem like a misguided kind of party trick if she didn’t pull it off so well. In those moments, it’s not just a legendary voice she’s channeling; it truly does feel like Garland’s heart and soul. B

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