It’s been three seasons and we still haven’t found out who killed Alison DiLaurentis (Sasha Pieterse) on ABC Family's Pretty Little Liars. So, we were expecting to gear up for a long wait until we found out who had killed Maya during the Season 2 finale. Luckily, Wetpaint Entertainment caught up with Janel Parrish (Mona) at the 2012 Teen Choice Awards on Sunday, July 22, who exclusively revealed to us that we will find out who killed Maya in the Season 3 summer finale.

Wetpaint Entertainment: What is going on in Mona’s world right now?
Janel Parrish: Mona is at the Radley Sanitarium, and I think the biggest question is, is she crazy, or is she not? What are her motives? And I think they constantly seem to change, which makes it so much fun for me because I can play so many different sides of her.

Do you know what her mindset is, or are you just going script by script?
I pretty much know. I don’t know everything, but I know what her mindset is.

What are we going to see in the near future?
All different sides, it’s just going to keep on going. You’re never going to know how you feel about Mona.

What about her visitors? Who’s going to be visiting her?
She’s going to get a couple more visitors that will make you fall out of your seat. So that’s coming up.

I’m hearing great things about the Halloween episode. Is there anything you can tease?
Adam Lambert will be performing. It’s on a Halloween train. So what’s not to love about that?

Where’s this train going?
That’s the question.

Is Mona involved in the Halloween episode?
She is in the episode, yes. So you will see what all her involvement may be.

But hopefully, not on the train.
Hopefully not.

Anything you can tease about the season finale?
You will find out who killed Maya.

We will?
Yes. You will, a hundred percent, you will find out.

Was that shocking to read? What was your reaction?
Absolutely shocking. My mind was blown. I can’t even formulate a sentence.

More blown than when you found out you were the villain to end all villains?
More blown because I kind of knew that was coming. This one, I was just like, “What? Are you kidding?” It’s going to be crazy. You guys will love it.

Find more Pretty Little Liars spoilers here.

Catch an all-new episode of PLL on Tuesday, July 24 at 8 p.m. ET/PT on ABC Family.

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