Katherine Heigl Opens Up About Joining Suits After Meghan Markle’s Departure: 'It Blew My Mind'

Katherine Heigl has been a working actress since she was a child, but her arrival to the set of Suits — where she was joining the cast for its eighth season following the departure of original stars Patrick J. Adams and Meghan Markle — was a new experience entirely, one that surprised even her.

“The first time I actually walked on the stages, and it sort of blew my mind,” she tells PEOPLE in its latest issue. “It was so strange to almost dive into my TV screen and be in the world that I’ve been fascinated by for years now.”

She adds, laughing, “I don’t know why my mind is so blown, I’ve been doing this my whole life.”

Heigl, 39, joins the series as a sharp lawyer named Samantha Wheeler, who is poised to butt heads with some of the already existing members of the show’s firm, currently known as Specter Litt.

“I love that Samantha is unapologetic,” Heigl explains. “She makes a misstep, she can say she’s sorry, she can acknowledge when she’s wrong, but she moves forward in life not being afraid of being wrong, not afraid of failing, and not afraid of ruffling feathers. And she kind of does it all a little like she’s got something up her sleeve.”

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Being part of a show that features several powerful female characters — like Sarah Rafferty’s Donna Paulsen, Markle’s Rachel Zane, and Gina Torres’ Jessica Pearson (who is getting her own spin-off series) — was certainly part of Suits‘ appeal for Heigl, who was a fan of the show long before joining the cast.

For more from Katherine Heigl, pick up the latest issue of PEOPLE, on newsstands Friday.

“Their femininity is celebrated,” she says. “It’s part of what makes them so good at what they do, so valuable to the firm. They’re not trying to change those parts of themselves to fit into a man’s world — it’s why they’re successful. It’s because of those instincts, those intuitions. And it’s really awesome to see that.

“I don’t want to play a woman who’s successful in a man’s world because she’s acted like a man. I want to see her be successful because she’s a woman.”

Suits season 8 premieres July 18 at 9 p.m. on USA.