4 stars

In the Keanu Reeves-Sandra Bullock film Speed, audience adrenaline levels surged at a bus wired by a domestic terrorist to blow if the accelerator dropped below a certain speed, with Reeves impossibly tasked to keep the careening vehicle safely moving and the public around it unharmed.

That gripping set-up has nothing on the extended scenes in the second act of Rupert Goold's Judy Garland late-life biopic. Jessie Buckley's upright British personal assistant, tasked with babysitting Rene Zellweger's fading Hollywood star, attempts to coax, coerce, bully and tug the performer from hotel room to a nightclub stage.

Once Hollywood's little darling, Garland has been forced to leave children Lorna (Bella Ramsey) and Joey (Lewin Lloyd) with ex-husband Sidney Luft (Rufus Sewell) in Los Angeles to accept a month-long run in a British nightclub, a much-needed pay cheque that might help her buy a home for her children to live in.

But Garland, already enough of a mess of insecurities, and with access to her children riding on a successful season, knows her voice isn't what it was thanks to a tracheotomy and a lifetime of indulgence, and so we see her down a handful of barbiturates and a slug of gin and lock herself in a bathroom.

Were they the ones that keep you awake or send you over the rainbow? How much gin did she have? Will Garland's self-indulgent compulsion to self-destruction overwhelm her her professional training?

As Garland eventually takes the stage, I was on the edge of my seat.

Judy Garland's short and tragic life has been thoroughly mined for stage and screen.

Tom Edge's screenplay for Judy is drawn from the stage play End of the Rainbow which enjoyed its first run on the Sydney Opera House stage in 2005 with Caroline O'Connor in the Garland role.

The film is definitely enjoyable in its own right, but it is hard not to feel like the whole thing has been constructed to help fill Zellweger's mantlepiece with the future Oscar, Globe and handful of other awards this performance deserves.

She gets the tones just right. Literally, in that she does a wonderful job of Garland's vocal approach and range, and if the singing isn't perfect, neither was Garland's by this time. She manages the fractious ego, the subtle manipulations, and balances the inflections that are familiar to us from Garland's film and television work, with her own characterisation.

The camera is right in her face, a face that has had far too many words written about it for a range of reasons - too squinty, too much weight on it, not enough weight on it, has she had something done - and the viewer carries that knowledge into the cinema and thinks - this is a face that has lived a life, this is why Zellweger is the right face for this role. Or, at least, this viewer did.

A word of respect for the make-up team in building this characterisation. Just subtle work, of eyeliner caked on a bit too unevenly, or that looks slept-in, drops little hints.

How do anyone keep up with a possibly career re-defining performance like Zellweger's? Well, the rest of the cast does pretty fine keeping up.

Jessie Buckley from the recent series Chernobyl does a restrained job as the PR-slash-babysitter Rosalyn Wilder, sensibly understated to better allow Garland/Zellweger to adorably chew the scenery.

Finn Wittrock has the beauty and physicality for Mickey Deans, the charismatic entrepreneur who became Garland's fifth and final husband.

I wish more were done with Bella Ramsey's Lorna - Game of Thrones fans will barely recognise the young Lady of Bear Island as a suburban Hollywood pre-teen with doe eyes - but Liza's younger half-sister already has her own Garland tell-all, the mini-series Life with Judy Garland: Me and My Shadows with Judy Davis in the title role.

Liza Minnelli makes a brief appearance, played by Gemma-Leigh Devereux as a knowing pal to her mother.

In flashbacks, Darci Shaw appears as a younger Judy, setting up the fragile woman she would become and recalling hard interactions with Louis B. Mayer (Richard Cordery), her slave-driving stage mother and even a young Mickey Rooney (Gus Barry) gets a few chops, which is delightful because I loathe Rooney with the fiery passions of Hell.

Despite the manipulation by the industry that created her, what Goold sets up is the charge that existed between Garland and her audience, a charge that fuelled her when it seemed like there was nothing left, and he does this through a terrific set of musical numbers, all Garland standards.

Goold's film, much like the later Garland depicted, isn't perfect, isn't what it might have been, but it delivers a knockout punch.

Cinemas like to do a thing called counter-programming. When they have a violent film like Joker playing, it's nice to also be screening an animation for the kiddies and a safe-looking work for the Boomers. Something for everybody.

There's something nicely subversive knowing those who might tsk-tsk Joker will adore Zelweger and her antics in Judy, when in fact the parallels between the two films are many - both about damaged souls created by a ruthless and uncaring environment fighting back the only ways they know how.