The Orange Is the New Black actress told the Duchess of Sussex she's been a fan of hers since Suits

When Laverne Cox was asked to be a part of the September issue of British Vogue, titled “Forces for Change,” she had no idea that it was being guest-edited by Meghan Markle — and that the Duchess of Sussex had handpicked her for the cover.

“I did not find that out until last week,” Cox tells PEOPLE. “[British Vogue editor-in-chief] Edward Enninful called me at 9:30 in the morning and he’s like, ‘I have someone on the phone for you,’ and it was the Duchess of Sussex.”

“She was so lovely,” the trans rights activist and Orange Is the New Black star continues. “She just thanked me for being an inspiration and to keep it up.”

Meghan Markle, Laverne Cox
Credit: Chris Jackson/Getty Images; Nicholas Hunt/Getty Images

Cox even managed to tell Meghan that she has been a fan of hers since Suits.

“I did tell her I had been a fan of Suits since the beginning — I had been a fan of hers since then. I just loved her on the show. She just said, ‘Awww.’ She seemed surprised.”

LaVerne Cox Vogue
Laverne Cox

Meghan was a hands-on collaborator for the upcoming issue, which features 15 trailblazing women on the cover. Among the group are actors and models, politicians and authors, and advocates for everything from diversity and mental health to climate change and voting rights.

“It’s a dream come true,” Cox tells PEOPLE of making history as the first transgender British Vogue cover star. “It’s been one of my biggest dreams and here it is.”

Meghan Markle Duchess of Sussex Vogue
British Vogue guest-edited by Meghan Markle
| Credit: Peter Lindbergh/PA Wire

Cox also opened up about Meghan’s decision to include a “mirrored” sixteenth space in the center of the cover to reflect the reader.

“What’s exciting about the cover is the blank square where there’s a mirror,” she says. “Yes, all these women are an amazing force for change, but it really has to start with each individual. We need to come together as a human race and understand our shared humanity to save our planet and lift every voice and experience and every story. I believe that is the work.”

Meghan Harry Lion King
Meghan Markle and Prince Harry

Cox also notes the special legacy Meghan is now championing through her work.

“She has been such a huge inspiration for so many of us,” she says. “Yes, as an African American member of the royal family, but I think a lot about Prince Harry’s mother, Princess Diana, and what she meant to so many people. She wanted to help and be of service to the world — it feels like Prince Harry chose a partner who embodies so much of what his mother stood for. Certainly the Duchess is her own person, but I think about what it means to be of service. I feel like that’s what she feels called to do. And I think that’s a beautiful thing.”