“You won’t forget me, will you? Promise you won’t,” says Oscar winner Renée Zellweger in the new trailer for “Judy.”

The upcoming Judy Garland biopic looks at the life of the late legendary actress and singer, including her final marriage to manager Mickey Deans (Finn Wittrock of “American Horror Story”). The cast also includes breakout Brit star Jessie Buckley (“Wild Rose”) and veteran character actors Rufus Sewell and Michael Gambon. Rupert Goold (“True Story”) directs.

Set in 1968 — a year before Garland’s death at age 48 from a barbiturate overdose — the film details Garland’s time performing a five-week London nightclub run.

The one-minute promo clips opens years after her career peaks in “The Wizard of Oz” and “A Star Is Born,” with the star attempting to check into a hotel — until a desk clerk informs “Miss Garland” that her suite is not available because of unpaid bills. Turned away with her kids in tow, Judy pops some pills, spurring one daughter to ask her not to fall asleep.

“These are the other ones,” Zellweger claps back, expertly mimicking Judy’s punchy vocal delivery.

As the iconic performer struggles to juggle motherhood, addiction and her flagging career, she gets a last-ditch offer to gig at Talk of the Town in the UK. “You’re saying I have to leave my children if I want to make enough money to be with my children?,” Judy asks before booking the final shows of her tragic life.

The trailer also features Zellweger, 50, singing on screen for the first time since her Oscar-nominated turn as Roxie Hart in “Chicago.” She interprets some of Garland’s most iconic songs, including “Somewhere Over the Rainbow” and “The Trolley Song.”

The film’s costume department had their work cut out for them but rose to the task, replicating the orange silk Garland wore at the Palace Theater in 1967, the blue and feathered outfit she wore at her wedding to Deans, and other iconic looks.

“Judy” is set to hit theaters Sept. 27.