By Natalie Abrams
April 04, 2017 at 04:01 PM EDT

When Fox’s Prison Break revival launches in Spring 2017, nearly all the beloved characters from the original will return, as Michael Scofield (Wentworth Miller) goes on an Odyssey-inspired journey to get home to his brother, Lincoln Burrows (Dominic Purcell), his former wife, Sara Tancredi (Sarah Wayne Callies), and his son, Mike (Christian Michael Cooper).

Although reuniting the Prison Break team wasn’t met with Odyssey-level obstacles, there was certainly trepidation among the cast. Callies says she was probably the last actor to sign on. The Walking Dead alum — who is now starring on USA Network’s Colony — wanted to make sure the revival wasn’t just about “a bunch of actors and executive producers who want to cash some old checks,” she tells EW. “My first thought was, it better be good.”

Actually, Callies’ first thought was something very different. The actress recalls initially learning about the possibility of a Prison Break revival from Girlfriends Guide to Divorce star Paul Adelstein — who played Kellerman on the original series and will appear in the update — at an upfronts party in New York. “He said something on the order of, ‘Have you heard that they’re bringing Prison Break back?’ What I said, I guarantee you can’t print.”

Challenge accepted.

“It was, ‘No f—ing way, holy f—ing s—,’ like expletive filled. Totally did not believe it, like not in a million years, because I asked the same questions that everybody’s asking,” she says. “They’re like, ‘But Michael’s dead?!'” — a response that’s somewhat ironic for Callies to have considering her character’s head ended up in a box in the series, yet Sara later returned with her noggin intact. “Yeah, okay,” Callies says with a laugh. “To be fair, Walking Dead was not the first show that I was on where people get resurrected constantly.”

The actress was convinced the revival was real when Prison Break executive producer Dawn Olmstead (now the executive vice president of development at Universal Cable Productions) approached her later at that same party and asked to do lunch. “I was like, ‘Okay, all right, this is not a coincidence.'”

But Callies “played really hard to get,” she says. “Prison Break meant a tremendous amount to me personally, and I have a job, so I only want to come back if we’re doing something brave.” Part of her hesitation was what it meant to actually inhabit this role again. “Personally, there was also a thought that Prison Break was my first real job,” she says. “I had only been in the business a couple of years, and it’s been seven years since I left that show. I ought to be a better actor by now, you know?”

“Andy Lincoln and Jon Bernthal are two of the best teachers I’ve ever had,” Callie continues, “not that any of them ever tried to teach me anything, but I’ve learned so much on Walking Dead, on Colony, on weird little movies with Nic Cage and stuff. I guess I’m interested to see if I can do better than I did before. I realize I’m setting myself up to be completely panned. ‘Guess what? She didn’t learn s—,’ but I hope I’m a better actor and I hope I can bring more to it than I did before, so that, to me, seems like a legitimate reason to do it.”

The other reason to do it was reuniting with Prison Break creator Paul Scheuring. “A huge part of wanting to come back was that Paul was the brain behind it, and this was always Paul’s baby,” Callies says. “Paul kept saying, ‘I want to get back to what we tried to do that first season.’ Season 1 was the best season we had. It was smart, it was brave, it was direct, it wasn’t coy.”

Though the revival is inspired by the early days, Callies insists Sara is a much different character. “When we left her, she was a young woman devastated by losing the love of her life, and she was pregnant, and when we meet her again, she’s seasoned,” the actress says. “She’s moved through her grief to the point where she realized that her grief was an extravagance her son couldn’t afford, and so she decided to make him her life’s work, and honors the legacy of his dead father by giving him a good life; that includes giving him a stepfather [played by Mark Feuerstein]. She’s changed hugely, just as I have. I don’t think I could play a facsimile of Sara Tancredi from season 1, but playing Sara Scofield in season 5 is both different and honest.”

Once shooting kicked off in early April, all fears immediately evaporated on day one. “There’ve been divorces, marriages, coming-outs, babies, career changes, and yet the things about these people remain essential,” Callies says. “It was an emotional day. Our director came up to me and was like, ‘You have to stop crying. Sara is not losing her s— in this moment.’ I was like, ‘Okay, I’m trying. This is actually not an acting choice.’”

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