The 'Duke' actress made her way onto a number of best-dressed lists thanks to the floor-length pink Dolce Gabbana gown - which featured floral detail on the shoulder and at the waist - and matching headband she wore to the ceremony in February.
She explained that the event allowed her to live out her teenage fashion fantasies.
She told W magazine: "I realised I was sort of channelling the prom dress that I never got to wear. I never got to go to the prom because we don’t have proms in England. So it was kind of like a dream prom dress."
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The 76-year-old star has regularly walked the runway for L'Oreal in recent years, but she thinks actresses are "hopeless" at such shows when compared to "haughty" models.
"Actresses, we’re hopeless. Models don’t feel the need to communicate with the audience, whereas an actress feels that we have to communicate with the audience," she said.
"They hold themselves above and beyond the audience, which is rather wonderful. They never smile; they’re haughty if you like. And normal actresses go on the runway, and they’re immediately smiling."
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Helen insisted she isn't a "fashionista,” but she just loves beautiful things.
"I’m very visual. I’m much more visual than I am aural, actually. I don’t really listen to music, [which is a] terrible confession. But I love looking. I get incredible visual pleasure from just a tree or a sunset or a city street. I love photography, I love ballet. And I love art and going to art exhibitions. I find it very renewing and revealing," she said.
"I think it’s another reason I love clothes. I love going to fashion shows. It’s not that I’m a fashionista, I’m not. I get very lucky, and I get many beautiful things, but in my normal life, I’m not really a fashionista at all. But I love the creativity, artisanal, and just visuals of fashion, the way shape, colour, and form constantly change."
Source: W magazine
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