“Judy” is a marvelous and complex biographical portrait of movie icon and pop singer Judy Garland.

The movie is a behind-the-scenes glimpse of Judy Garland, best-known for her starring role as Dorothy in “The Wizard of Oz” (1939) and her rendition in that movie of “Somewhere Over the Rainbow,” a song with which she would always be identified.

Garland, born Frances Ethel Gumm, June 10, 1922, died at age 47 on June 22, 1969, in London from an apparent accidental barbiturate overdose.

Garland’s death happened six months after her five-week booking at the Talk of the Town nightclub in London.

“Judy” concentrates on the last months of Garland’s life when she was down on her luck, down on her finances, and taken down by her apparent prescription-drug dependency and alcohol abuse.

The movie includes many flashbacks to the young Judy Garland during her early years at MGM Studios when she landed the role of Dorothy in “The Wizard of Oz.”

The flashback structure in “Judy” is not altogether successful. However, it was probably necessary to provide biographical information.

“Judy” is directed by Rupert Goold (director, TV’s “King Charles III,” 2012), from a screenplay by Tom Edge (Netflix’s “The Crown,” 2016-present) based on the stage play, “End of the Rainbow” (2011) by Peter Quilter.

The storyline in “Judy” alleges that MGM studio boss Louis B. Mayer (Richard Cordery) and Garland’s studio handlers got Garland hooked on uppers and downers in an attempt to control her weight, and keep her working long hours at the movie studio. The young Judy Garland is played by Darci Shaw.

Key scenes in the film circa 1968 include Garland’s alleged acrimonious relationship with her third husband, Sid Luft (Rufus Sewell), and her romance and falling out with her fifth and last husband, Mickey Deans (Finn Wittrock). Her then young daughter, Lorna Luft (Bella Ramsey), and her then young son, Joey Luft (Lewin Lloyd), are also in significant scenes. Jessie Buckley has considerable screen time as Garland’s London concerts’ assistant, Rosalyn Wilder.

The flashbacks provide important background by way of providing an understanding of the possible reasons for Garland’s erratic behavior throughout much of her Hollywood movie career, the decline in her box-office draw status and her falling into poor health and probable depression toward the end of her life. Most of these aspects about Garland’s career and life are well-known, but probably necessary for the non-Garland fan and casual moviegoer.

However, the flashbacks are jarring because, while Darci Shaw is good as the young Judy Garland, she’s no Renée Zellweger, who plays Judy Garland in the title role with unmatched zeal. Zellweger is so good, believable and dynamic as the older Garland that you can’t help compare her performance to that of Darci Shaw’s, which is flat in comparison.

Zellweger is amazing as Judy Garland. She has Garland’s body tics, mannerisms and facial gestures down to a T. These include a slouchy stance, jerky, seemingly spastic arm movements and jittery hand gestures, even while singing; the pursy lips that morph from a Betty Boop smile to a kissy pout; a scrunched-up face, and squinty eyes that peer out with a mixture of aching need and steely disdain.

Zellweger also has Garland’s vocal inflections down, which switch from an unctuous purr, to charming compliments and quips, to poor, pitiful me angry rants of self-loathing, remorse and resentment.

Moreover, Zellweger sings Judy Garland’s songs exceptionally, including, of course, “Somewhere Over the Rainbow,” and also “Get Happy,” “The Trolley Song,” and “Come Rain or Come Shine.”

It should come as no surprise that Zellweger is up to the task of portraying Judy Garland. Zellweger received a supporting actress Oscar for “Cold Mountain” (2003) and actress Oscar nominations for “Bridget Jones’s Diary” (2001) and “Chicago” (2002), the latter for which her singing and dancing chops were much on display in her role as Roxie Hart.

Zellweger subsumes herself in the role of Judy Garland in “Judy,” much like “Rocketman” (2019), starring Taron Egerton as Elton John, who did his own singing, and “Bohemian Rhapsody” (2018), starring Rami Malek as Freddie Mercury, who did not do his own singing (and received an actor Oscar).

This is a landmark performance by Renée Zellweger as Judy Garland in a landmark film. Zellweger deserves an actress Oscar nomination. And the Oscar should go to Renée Zellweger for Renée ... and for Judy.

“Judy,”

MPAA rated PG-13 (Parents Strongly Cautioned Some material may be inappropriate for children under 13. Parents are urged to be cautious. Some material may be inappropriate for pre-teenagers.) for substance abuse, thematic content, some strong language, and smoking; Genre: Biography, Drama, History; Run time: 1 hr., 58 mins. Distributed by Roadside Attractions.

Credit Readers Anonymous:

“Judy” was filmed in London.

Box Office,

Oct. 11-13: “The Joker” continued at No. 1, two weeks in a row, with a strong $55 million, $192.7 million, keeping the opening of those other monstrous jokers, albeit a newly minted animation crew, “The Addams Family,” opening at No. 2 with $30.2 million, and splitting the other new opening, the Will Smith meets his younger CGI self, “Gemini Man,” opening rather weakly at No. 3 with $20.5 million.

4. “Abominable” slid down two places, No. 4, with $6.1 million, $47.9 million, three weeks. 5. “Downton Abbey” stepped down two places, $4.9 million, $82.6 million, four weeks. 6. “Hustlers” danced down two places, $3.8 million, $98 million, five weeks. 7. “Judy” stayed in place, $3.2 million, $14.9 million, three weeks. 8. “It Chapter Two” ran down three places, $3.2 million, $207.1 million, six weeks. 9. “Jexi,” $3.1 million, opening. 10. “Ad Astra” zoomed down four places, $1.9 million, $47 million, four weeks.

Unreel,

Oct. 18:

“Maleficent: Mistress of Evil,”

PG: Joachim Rønning directs Angelina Jolie, Teresa Mahoney, Michelle Pfeiffer and Elle Fanning in the adventure-fantasy film. In the sequel, Maleficent and her goddaughter Aurora face challenges, new forces and a wedding.

“Zombieland: Double Tap,”

R: Ruben Fleischer directs Zoey Deutch, Abigail Breslin, Emma Stone and Woody Harrelson in the comedy horror film. In the sequel, the gang is back to face smarter zombies.

“Jay and Silent Bob Reboot,”

R: Kevin Smith directs Melissa Benoist, Chris Hemsworth, Matt Damond Ben Affleck in the comedy. In the sequel, Jay and Silent Bob go Hollywood to try to stop a remake of a “Bluntman and Chronic” movie.

“Jojo Rabbit,”

PG-13: Taika Waititi directs Roman Griffin Davis, Thomasin McKenzie and Scarlett Johansson in the war drama. A soldier in Hitler’s army discovers his mother is hiding a Jewish girl.

Three popcorn boxes out of five.