The Insider.com

Two years worth of terrifying texts, omnipresent enemies, red herrings and disturbing dolls came to a head last night when Pretty Little Liars finally unmasked "A" -- revealing that Mona has been the one tormenting Aria, Hanna, Spencer and Emily since summer 2010!

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For some this reveal came as a shock, for others, the writing was on the wall -- especially over the last few weeks as Mona integrated herself in with the PLLs in a rather curious way. I mean, we never saw her get a single text from "A" and yet she kept showing up with lots of threatening messages.

This morning I sat down with actress Janel Parrish to talk all about this massive reveal, find out how difficult it was to keep the secret and see what lies ahead for the mastermind Mona in season three!

Insider.com: When did creator Marlene King tell you that Mona was "A"?
Janel Parrish: I actually found out in the pilot that Mona was probably going to be "A" because she was in the books. Producers kept it close to the vest and always said things could change, so I tried not to get too excited about it but I always hoped that was the way it would go. It would just be so cool to play such a complex character. I was so excited when I got this script. It is an honor to play such a pivotal character to the show. And so much fun!

Keegan Allen Plays "A" or B

Insider: You guys filmed this episode months ago -- how hard was it to keep the secret?
Janel: It was hard [laughs]. I wanted to tell everybody. I really wanted to. But it was so important that it stay secret for the fans. I didn't want to ruin it for anybody, especially the fans who tune in every week to be shocked and scared. It was important to all of us on the show that it stay secret until last night. And the payoff was worth it!

Marlene King Talks "A" Reveal

Insider: With the post-reveal car scene, what was important to you in that moment as an actor?
Janel: It was important to find the instant Mona switched from the girl who sing-songs everything she says to this crazy psycho person who is capable of murder. Just trying to find the switch in the character was my goal.

What's Up With Melissa?

Insider: But fans shouldn't take this to mean Mona killed Ali, right?
Janel: You'll just have to wait and see! Mona did say something about an A-Team, so you'll have to wait for season three to find out what she meant! But fans should never be surprised by anyone's connection in Rosewood – it's a small town, it's got a lot of devious people and I can tell you that people you would never think could be connected, are! I think that's where season three will take us.

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Insider: The ending moment saw Mona tell a mysterious figure, "I did everything you said." Do you know who she was talking to?
Janel: I do not. I have to wait for season three like everyone else. The premiere stars six months after the finale and you'll learn more about Mona's visitor and Mona will have a lot of explaining to do.

Insider: Will any of those explanations involve exactly how Mona carried out her "A" actions over the last two seasons?
Janel: Yes, explanations will be coming – as will a lot more questions. Per usual. We have to keep everyone guessing! But I'm really looking forward to explanations about how did Mona do all of this stuff. I'm curious to see myself.

Insider: Do you want Mona to find redemption or do you want her to keep being bad?
Janel: I kinda want her to be crazy because it's so much fun. It's a different color to the show. I love that PLL isn't just a teen drama like a lot of the other shows out there. It has a mystery aspect to it, and I think that's what keeps the fans tuning in. To be a part of that in any way is super exciting!