Renee Zellweger sings Somewhere Over The Rainbow as Judy Garland in the upcoming biopic’s first look.

In the trailer for Judy, Zellweger is almost unrecognisable, her usual blonde hair changed to a dark brown, as she takes on the role of famed singer and actress Garland.

Oscar-winner Zellweger lends her own voice to the film as she sings the legendary tune from The Wizard Of Oz, in which Garland played the starring role of Dorothy.

Throughout the short trailer released on Friday, the Bridget Jones actress is seen singing on stage in a movie montage of Garland’s life.

Viewers also get a first glimpse of Finn Wittrock as Mickey Dean, who the star married several months before her death in June 1969 aged 47.

Harry Potter actor Sir Michael Gambon and War And Peace actress Jessie Buckley also star in the feature film, which is directed by double Olivier Award-winner Rupert Goold.

Judy is set in 1968 and tells the story of Garland arriving in London to perform in a sell-out run at The Talk Of The Town nightclub, 30 years after her rise to fame in The Wizard Of Oz.

Zellweger in character as Judy Garland (Pathe UK/PA) Zellweger in character as Judy Garland (Pathe UK/PA)

The film shows the charismatic yet fragile star’s battle with management while dealing with the struggle of spending her whole life in the spotlight, and her yearning to be at home with her children.

Judy, a joint venture between Pathe, BBC Films and Ingenious Media, includes some of Garland’s best-loved tunes.

Goold said: “For over 40 years Judy Garland had laughed and loved and entertained no matter what life threw at her, and her public adored her for it.

“But she paid a price in a childhood lost to Hollywood, an emotional exhaustion and a yearning for a ‘normal’ life beyond the rainbow.

“It is a powerful and moving story that I hope will inspire new audiences to discover Judy Garland’s joyous legacy.”

On Zellweger playing Garland, the director said: “I felt Renee was uniquely qualified to play Judy.

“First, because she is a great, Oscar-winning dramatic actress. Second, she is a wonderful comedienne.

“And third, I knew from Chicago that she could sing.

“I made it clear to Renee that I wasn’t looking for an impersonation of Judy Garland’s inimitable voice, but what I wanted was for Renee to make the songs her own and this she did to thrilling effect.”

Judy is due to be released on October 4 2019.