Lady Gaga presents Harley Quinn with her fiancé Michael Polansky at the premiere of “Joker Folie à Deux” in London

Leave it to Lady Gaga to close a red carpet.

On Wednesday, September 25, the 38-year-old superstar had a glamorous date night with her fiancé Michael Polansky at the London premiere of her new film Joker: Folie à Deux. She also posed for photos with her co-star Joaquin Phoenix.

The actress portrayed her role as Harley Quinn in a dramatic red dress by Celine by Hedi Slimane. Polansky wore a classic black suit from Celine Homme by Hedi Slimane.

Gaga's floor-length dress featured a V-neckline and a pleated skirt. The singer wore a cropped long-sleeved jacket with voluminous puffed sleeves. Her jewelry from Tiffany & Co. elevated the look even further; She was accessorized with a Jean Schlumberger by Tiffany Bird on a Rock brooch, Vigne ring, bracelet, and earrings in platinum and 18-karat yellow gold with Fancy Intense Yellow diamonds.

In a nod to her character's iconic makeup look, the star wore theatrical makeup consisting of turquoise eyeshadow, winged eyeliner, and a crystal teardrop under one eye. Plus, she's still sporting the bleached eyebrows she debuted in August. To complete the look, the “Bad Romance” singer wore red lipstick that matched her dress.

Her hairstyle also matched her outfit. In a departure from the icy blonde color she wore to the Venice Film Festival earlier this month, Gaga opted for a black bob cut with red highlights and short bangs.

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Gaga and Polansky, who went public with their relationship in 2020, made their red carpet debut at the premiere of ” Joker: Folie à Deux on September 4th.

At the Italian event, the star stole the show in a voluminous black dress with a plunging neckline and full skirt. The standout element, however, was her glittering lace headpiece by Philip Treacy. She accessorized with jewelry from Tiffany & Co. and platform boots.

Joker: Folie à Deux is a sequel to 2019 Joker. The film premieres on October 4th and tells the backstory of Phoenix's Joker and his love story with Harley Quinn, a role previously played by Margot Robbie, Mia Sara and Kaley Cuoco.

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“My version of Harley is mine and it's very authentic to this film and these characters and I don't want to give anything away from the film,” she said Access Hollywood on the red carpet of her Gaga Chromatica ball Screening and dance party on May 23rd. “I think you really have to experience that in the theater.”

“This film has music, it has dancing, it has great acting,” she added. “I loved working with Joaquin, I loved working with him [director] Todd [Phillips]. What I have to say is that I have never done anything like this film before, so everything will be completely new and really fun.”