How the Pretty Little Liars cast kept all those secrets

Watch the full interview with the cast of Pretty Little Liars here on the new People/Entertainment Weekly Network (PEN). Go to PEOPLE.com/PEN, or download the free app on your Smart TV, mobile and web devices.

Nobody is better at keeping a secret than a Pretty Little Liar, and we’re not just talking about within the fictional world of Rosewood. Outside of the show, the cast learned early on that they couldn’t reveal much plot, and with the exception of showrunner I. Marlene King, everyone claims to have made it seven seasons without letting a spoiler slip.

“I’ve only let something slip one time and it was you in the orange jumpsuit,” King says, pointing to Ashley Benson (Hannah). “You came to a meeting in your orange jumpsuit and I lied because it was around Halloween. I said, ‘No no, we’re dressing up for Halloween,’ but fans knew. That’s the only time I’ve screwed up.”

But keeping so many secrets for so many years has led the cast to try some unconventional methods to keep fans in the dark. “I feel like in the past I’ve definitely said the truth about some things because I knew people wouldn’t believe me,” Troian Bellisario (Spencer) says. “That was the best way to keep the secret — to bluntly say exactly what would happen and then say, ‘But can you ever trust me?’ And because I’ve been on a show with the word ‘liar’ in the title, nobody believed me! I think I said it about, like, Mona at one point.”

King adds, “In the age of social media, we’ve been really lucky that nobody has, excluding me that time with Hanna in the orange jumpsuit, messed anything up.”

Pretty Little Liars airs Tuesdays at 8 p.m. ET on Freeform.