Its initial half hour or so feels like we’re heading into “Under the Volcano”/”Leaving Las Vegas” territory.

The last 15 minutes, the tone is more “Mr. Holland’s Opus.”

Deep in the middle of “Judy,” though, is the sweet spot–a wonderful sequence with two fans where the film briefly clicks, giving a sense of both who Judy Garland was and why she was loved.

Beyond that, the film–and its lead performer–never finds its rhythm. Judy

It’s a gutsy choice, opening the film with Garland at her least sympathetic. Dragging her kids around as props in her show, popping pills, getting kicked out of a hotel for lack of payment, dumping her son and daughter at the house of their father before heading to a party herself. It’s easy to imagine an audience not fully versed in Garland-lore wondering what all the fuss about her is about.

Flashbacks attempt to get to the root of the issue, making clear the manipulated by studio boss Louis B. Mayer leading her into a cycle of uppers and downers. Scolded for eating, overworked on movie sets, and denied the opportunity to have anything resembling a normal childhood, Garland’s challenges are made very clear.

The downside of the flashbacks, though (in addition to being stylistically inconsistent) is that they breakup the performance of elder Judy, Renee Zellweger. Every time we return to her, it feels like a restart.

That might not be a problem if Zellweger were more believable in the part. She has the moves and the ticks down pat–and there are moments that will play strongly when clips are shown on a publicity tour. But she never fully becomes Judy. Perhaps I’m spoiled having just seen Michelle Williams’ transformational performance as Gwen Verdon in “Fosse/Verdon,” but with Zellwegger, I always felt like I was watching an actor really, really trying rather than succeeding in a brutally difficult part.

In the musical numbers, which don’t kick in until mid-film, the challenges are compounded by editing and direction that never quite sync. And while the actress can carry the tunes, she’s playing a superstar. Zellweger simply doesn’t have that special something as a musical performer. And, in spite of her valiant efforts, it shows.