The stars of Pretty Little Liars are not unlike their onscreen alter-egos.

Shay Mitchell, 24, tells BULLETT's spring issue she "was the queen about lying where I was" when she was a high school student. "I would be at a party, but as soon as my parents called, I would run out into the quietest part of the forest or wherever and be like, 'Hi! I'm just at home. Huh? I'm so tired. I'm going to bed."

VIDEO: Shay Mitchell takes Us behind-the-scenes of Pretty Little Liars

"You lie when you're a teenager, I think, because your parents are treating you like you're younger and you -- in your mind -- think that you're so much older," Mitchell explains. "You make up all of these lies because you think it's what you should do."

Costar Lucy Hale, 22, insists that she's never gone to the lengths her character has in order to keep a secret. "The lies that these girls tell are pretty extreme. I don't think what they are going through is normal," she says. "But little white lies here and there is human nature. Everybody does that."

PHOTOS: What the characters wore on Pretty Little Liars

Such as? "I definitely used to lie about my age. I'm from Tennessee and everyone would vacation in Destin, Florida, where there are lots of cute guys," she tells BULLETT. "I would go with my older sister and lie about my age to them."

There are some major differences between the stars and their TV personas, however. According to Sasha Pieterse, who plays Alison DiLaurentis, she was never a "mean girl" in high school.

VIDEO: Watch Shay Mitchell get ready for an awards show

"Alison is very protective of her friends because she has kind of handpicked them. She knows how to handle them, which is of course manipulative, but at the same time, she really does care about them," Pieterse, 16, explains. "As much as Alison picks on Hanna (Ashley Benson), she doesn't like when other people pick on her. She's almost like an older sister. At some point, she will do something that will protect them. There will be other enemies who will try to trash on them."

Get more Us! Follow us on Twitter, Friend us on Facebook, Subscribe to Us Weekly