Shay Mitchell: 'A' Will Take People Out!

We're mere hours away from the Pretty Little Liars season four premiere -- a year that will, by all accounts, be the show's darkest yet!

To find out what else lies in wait for fans, I hit up the set and sat down with the stars to talks cliffhangers, trunks, breakups and disappearing characters. You've already caught up with Ashley Benson and Lucy Hale, so today it's Shay Mitchell's turn!

ETonline: What was your reaction to finding out what is in the trunk?
Shay Mitchell: Shocked! And curious as to what it means for the show. Also, as Shay, I'm curious as to the process of the whole thing happened. We were all shocked, but we all wished that thing in the trunk had been there when filmed the finale, because there was nothing in the trunk that day and had we known what was in there, I think the reactions would have been different. But either way, it's very whoa.

ETonline: Your co-stars have said that what's in the trunk pushes this season to a much darker place. Do you agree?
Mitchell: Totally. Definitely. It really does set the tone for this season. A lot of people have questions about what it was, who it was, whatever. But no matter what, it opens the door for us to get way darker in season four. I mean, every finale is crazy but this takes a huge piece out of the puzzle. Now the girls have to search harder than they ever did before.

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ETonline: What does that mean for how "A" interacts with the girls?
Mitchell: The stakes are definitely raised and text messages are the least of their worries. I mean, when the phone rings now, they're like "Yes! Thank God! She's communicating!" A text is what we want this season because it gets so much worse. "A" has been working up to this for a long time; first it was a text, then it was killing off a girlfriend, now it's something else entirely. "A" is really intertwining herself in the girls' lives and their families' lives. It's really hitting home now.

ETonline: For someone who has kept so much of this from her family, how does Emily handle that?
Mitchell: Not very well [laughs]. Emily's parents are really feeling the repercussions of Emily not speaking out so now it's come to the point where they're like, "What's going on? You've kept so much from us!" Her parents are really feeling the pressure in a different way. But, it's still tough for the girls because if you tell someone about "A" they're probably going to get hurt. And it's gotten to a point where the girls know "A" is not joking around. She will take people out.

ETonline: Many of the girls think they saw Ali in the finale, where's Emily's head at?
Mitchell: Emily had her own flashback where she felt like she did see Ali in the barn, so she knows what the girls are feeling, but Emily really wants to put this to rest because she can't keep having her heart ripped out by the potential that Ali is alive. As much as she could believe the girls saw her, she still wants to put it away.

ETonline: And Toby?
Mitchell: Emily has always known that Toby is a good person. Even when Spencer thought he was on The "A" Team, Emily knew there was a reason he did that. Emily always will have Toby's back. She's known from day one that he’s a good guy, and he sees that in her. Thank goodness for Emily this season because she really helps keep them together when Spencer is unsure of Toby's motives.

ETonline: Mona has also become the fifth member of the group now -- how does Emily feel about that?
Mitchell: I don't think Emily will ever trust Mona. They couldn't be more different from one another. Even when Emily hung out with Mona before, she never trusted her. So now that she's tried to kill them all, at some point, Emily doesn't think anyone should trust her. But, she knows Mona has important information, so Emily will definitely use Mona this season. They need to get clues from Mona, they need to have Mona take them to her creepy office, so by welcoming her into the group, Emily is able to keep her eye on Mona.

ETonline: Emily also found out some interesting things about Jenna, Melissa and Shana in the finale. Is that information she shares with the group?
Mitchell: Yeah it is. I'm starting to call her Detective Fields this season because Emily is really the one putting lots of pieces together, especially with those three girls given how much Emily knows Shanna from the swim team. So she really thinks it's weird that she's getting so close to them. Emily now knows something is not right with Shana. Although, Emily is dealing with a lot already, so to have whatever those three are plotting thrown into the mix is kind of overwhelming.

ETonline: With all that, how does Paige fit in? Is she kind of like Emily's safe haven in this storm?
Mitchell: Yes, Paige is the one person Emily can fall back on for a bit of normalcy. Their lives are so messed up and one of the girls is always on the verge of getting a text message, so when she's with Paige, she's semi-removed from the drama. Emily has chosen to tell Paige little things here and there, but Emily is still very protective of Paige -- especially given her history with girlfriends. I mean, I would never date Emily! She's like the black widow of Rosewood [laughs].

The Ultimate Pretty Little Liars Premiere Guide!

Check out all of ETonline's PLL Coverage Below:

Ashley Benson Interview

Lucy Hale Interview

Troian Bellisario Interview

Marlene King Talks Ravenswood

PLL Season Four Clips

PLL Season Four Trailer

PLL EP Answers All Your Burning Season Three Finale Questions

Watch Paige & Caleb's Unaired "A" Reveals

Meet Aria's New Love Interest

Pretty Little Liars premieres tonight at 8 p.m. on ABC Family.