Spoiler warning: If you haven’t watched the season 5 premiere ofYounger, continue reading at your own risk.

The momentYoungerfans have been waiting for for four seasons has finally arrived: Liza’s (Sutton Foster) boss and love interest Charles (Peter Hermann) knows her real age.

On Tuesday night’sseason premiere, Empirical Publishing owner Charles learned that Liza — who got hired as an assistant under the guise that she was 25 — is actually in her 40s.

“It’s huge,”YoungerstarHilary Dufftold PEOPLE of the reveal during the show’s New York City press day in April.

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Though fans will have to wait until the next episode to find out how he reacts, Duff said the fallout is “scary for Kelsey,”her character.

“As much as she loves Liza, she’s worked really hard to get where she is and she continues to put her at risk,” the mom to 6-year-old son Luca continued. “I think she’s kind of sick of it. I don’t think Kelsey loves being a liar with Liza. It makes them look like frauds.”

With the secret getting out around the office, Kelsey doesn’t want her credibility to be questioned.

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But Duff said that unfortunately, “Everything’s going to come out.”

Kelseymight also consider leaving the publishing house, where she runs the successful Millennial imprint.

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“She’s definitely considering it,” theformer teen starteased. “You never know what Kelsey’s capable of. She’s a little bit of a wild card. As much as he wants to push ahead, I don’t think she’s above doing something that makes her really uncomfortable, like maybe leaving a job and having to work her way up again. She holds a lot of worth at the company though and they know that, so well see how far she gets with that.”

source: people.com