Not just because she was getting her feet wet playing the iconic role of Ariel and starring in a massive film production for the first time—or even because she had to remember to look to the right instead of left when crossing the street and that elevators are called "lifts." Rather, living across the pond meant spending far more time than usual away from her big sister Chloe Bailey.
"I am so used to being with my sister, who's my angel, who's my rock, who's my other arm," Halle told E! News' Francesca Amiker in an exclusive interview. "But filming this movie was really a moment about, 'Okay, Halle, you can do it, you got to learn how to do things on your own."
And the journey ultimately resulted in a surge of self-confidence for the 22-year-old, the younger half of singing duo Chloe x Halle by 20 months.
"I've never had that college experience because I've been on the road since I was 13 years old," Halle explained. "So this was like, 'You're getting your wings, you be free by yourself, fly!'"
That independence—combined with playing one of the most defiant Disney princesses in the land—found its way into the new solo music she's been working on for the past two years.
"I truly feel that being Ariel helped me identify who I am on my own," Halle said. (Unlike Ariel, however, she "didn't want to get out ever" from the 89 degree water in the massive tank that stood in for the mermaid's oceanic home, one of her favorite parts of filming.) "The experience of doing that really inspired me creatively and I put everything I was feeling into the music, because that's the way I express myself the best."
But Halle of course remains her sister's No. 1 hype woman, championing Chloe's upcoming album, In Pieces, due out March 31, and applauding the 24-year-old's performance in her "amazing" Amazon Prime series Swarm.
"My sister is so multitalented," Halle gushed, "and people see how amazingly talented she is, as well as her beauty, and I'm just proud of her."
So we know who'll be cheering the loudest when The Little Mermaid finally comes out, though it'll be a toss-up as to which Bailey sibling is crying more of a river: Chloe has said she teared up when she saw Halle's screen test, knowing her little sis would be the perfect Ariel, and Halle admittedly sobbed for 20 minutes when she saw the first cut of the film.
"It's this very weird, out-of-body thing," Halle told E!. "I've never seen myself on a big screen like this. So number one, it's weird to watch yourself. But then you're also like, 'Who is this girl, who's a mermaid, who's doing a great job—like, I did this?'"
That she did, and she's got the keepsakes to prove it—though enjoyable time flipping her fins aside, Halle said with a smile that she "did not take the tail" home with her.
Though she still has whozits and whatzits galore. She was gifted a "beautiful" corset piece from one of Ariel's gowns by the film's costume designer, four-time Oscar winner Colleen Atwood. And Halle remains betrothed to her Disney prince in spirit: "The ring that she gets from Eric," she shared, "I have it."
But souvenirs are no big deal when a star is in the middle of a major sea change.
The Little Mermaid hype has been building since the day Halle was announced as the choice to play Ariel in 2019, and finally she's in the homestretch.
"It's been so exciting and very surreal to see people's reactions and hear their feedback, because I've worked so hard on this for so very long," Halle said, reflecting on the Oscar night release of the biggest trailer yet for director Rob Marshall's reimagining of the 1989 animated classic. "To finally see the rollout start to happen, it's dream-like—and I just cannot wait until it's out-out in May."
That's May 26, for anyone who may have been asleep inside a giant clamshell for the last few months. So that means the star still has a press gauntlet ahead, for which she'll need to keep her energy up and her enviable voice in full working order. And with spring officially sprung, that means adding Zyrtec to her wellness regimen to keep allergy symptoms at bay, her latest collab with the brand on its Beat the Mondays Tour a natural fit for the singer, actress and cat mom to baby Poseidon.
"I will cuddle with him," she said defiantly. "I will stuff my face in his whole body—and yeah, my allergies flare up! But I don't care because I love cats. Zyrtec helps me get through those moments."
But tissues may be necessary even in pollen-free zones.
Halle shared that she also got emotional watching herself onscreen because she was thinking of everything her family has done for her to help her get to this place, plus, "all the doors that have been opened by other inspirational Black women just allowing me to be here today."
And when her Ariel doll was released earlier this month to much fanfare...
"I cried, once again," Halle said. "I've been crying a lot, just out of gratitude. I was speechless because seeing yourself in a doll is essential to our growth, our self-worth, our confidence. And I know that if I had that when I was 5, it would have changed my whole perspective."