Only one of them was an actual mother. Ms. Ferguson reminded me of this on Sunday, when she called from her hotel hallway. She had stepped out of her room so that her 5-year-old daughter could sleep and discovered that the hallway bore an unsettling resemblance to the one in “The Shining.”

Still, she didn’t feel like the “Dune” fashion-palooza had really prepared her for the Met Gala.

“This is something that stands alone,” Ms. Ferguson said. “It’s a free bird of craziness.”

Funny she should mention birds. Her Met Gala dress was covered in them.

After wearing Thom Browne at least twice to promote “Dune,” Ms. Ferguson arrived on the Met steps on Monday wearing one of his more theatrical creations. A black silk moiré floor-length cape undulated from her shoulders.

The lining of the cape was embroidered with ravens. So was the sequined high-neck gown underneath. The hips and shoulders of the dress were exaggerated in a way that made her feel “powerful,” Ms. Ferguson said. The whole ensemble was covered in 60,000 green and blue Swarovski crystals embroidered into flowers. (This is one of those garments that designers proudly provide numbers for. At least 30 people worked on it for 8,500 hours.)

Ravens were a motif in Mr. Browne’s most recent runway show, which took some inspiration from Edgar Allan Poe’s “The Raven.” Ms. Ferguson said she spent some time trying to “analyze” the poem in relation to “The Garden of Time,” the J.G. Ballard short story that inspired the Met Gala’s dress code.

“I was trying to combine all of this imagery of his poetry and the dress, and I was like, ‘I’m going too far. No one else is going to think about this,’” she said. “It’s free, it’s spiritual, it’s timeless.”

As for attending the gala for the first time, Ms. Ferguson said she was feeling overwhelmed by “the spectacle of it — to be invited is scary.” (Here, she used an expletive or two; she has a reputation for bluntness in interviews.)

“I feel like Bambi on ice,” she said. “And then at the same time, I feel so calm because I love what I’m wearing. And I’ve been so cradled by the Thom gang.”

Would channeling that “mother” persona help her get through the night?

Ms. Ferguson wouldn’t force it. The first time she heard someone say “mother is mothering,” she said she responded: “Oh, my mum’s fine. She’s home. She had some dental work, but she’s OK.”

“If you’re too aware of slaying, then I think you’re not slaying.”