Katie Leung Had Never Watched ‘Bridgerton’ Before She Was Cast in Season 4 (Exclusive)

Katie Leung didn’t exactly know what she was getting herself into when she joined Bridgerton.

The Harry Potter alum makes her regency debut in season 4 of the hit Netflix series as Lady Araminta, the evil stepmother in the Cinderella story that unfolds between housemaid Sophie Baek (Yerin Ha) and Benedict Bridgerton (Luke Thompson).

Leung, 38, tells PEOPLE she “hadn’t watched the show before I got the part,” which ended up coming in handy as she had a run-in with one of her future castmates that she wasn’t prepared for, but turned out to be a “funny story.”

“In between watching the first season and getting the part, I had to go in for fittings,” Leung recalls. “And I remember meeting Golda [Rosheuvel] in the makeup room, and she was getting this big wig fitted at the time, but I had no idea who she was.”

“She just was like, ‘Oh, hi Katie,’ and she was just super casual and lovely. And she asked me if I was nervous, and I was like, ‘No, not nervous.’ “

“It wasn’t until afterwards — when I started watching season 1 — I was like, ‘Oh my f—ing God, she’s the queen!’ ” Leung says.

“I was really glad that I hadn’t seen [the show] yet, because otherwise I would’ve been nervous and starstruck, and she’s so chill.”

Leung’s first meeting with Rosheuvel set the tone for how her entrance into the cast would go. “Everybody was so welcoming just from the get-go,” she says. “It just felt super seamless.”

It helped, too, that Leung wasn’t the only newbie around. Ha, 28, had just joined, and Michelle Mao and Isabella Wei, who play Leung’s on-screen daughters Rosamund and Posy, were also new.

“I think it really helped that I wasn’t the only one joining, there was a team of us, and we met up for HotPot before it all started, so that helped as well,” Leung says.

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Her smooth transition into the cast also meant that she “could just start focusing on the work.”

“Whenever you join a new project, it does always feel like the first day of school on the first day on set,” she admits. “I don’t know why, but on this occasion, on this project, I just got over that really quickly. So that was nice.”

Season 4 of Bridgerton focuses on the family’s “bohemian second son,” Benedict (Thompson), who is “loath to settle down,” despite his older brother’s happy marriages. That all changes, though, when Benedict “meets a captivating Lady in Silver at his mother’s masquerade ball,” per the official logline.

Jonathan Bailey, Nicola Coughlan, Luke Newton, Hannah Dodd, Claudia Jessie, Ruth Gemmell and Simone Ashley all return in season 4, alongside Florence Hunt, Will Tilston, Victor Alli, Adjoa Andoh, Masali Baduza and Daniel Francis.

Part 1 of Bridgerton season 4 premieres Thursday, Jan. 29, on Netflix, followed by Part 2 on Feb. 26.