On Pretty Little Liars Season 3, Episode 7: “Crazy,” Mona (Janel Parrish) gave Hanna (Ashley Benson) messages via code. While the Liars talked about two of Mona's messages —"Not Safe" and the website — a key message went undeciphered.

When Hanna and Aria (Lucy Hale) first walked in on Mona, she repeated the phrase "Miss Aria you're a killer, not Ezra's wife" several times. If we use Mona's code method — taking the first letter of every word — we can see this spells M-A-Y-A-K-N-E-W: "Maya Knew."

Cue our jaws dropping to the floor. This seems like a huge clue. Many people suspected that Maya (Bianca Lawson) was murdered for knowing too much, and this may just be confirmation of that. However, that still leaves the question: What did Maya know?

Here are our top five theories about what secret could have lead Maya to an untimely grave.

1. Who "A"/the "A" team was. Maya may have discovered Mona's secret, or the secret of the new "A", or the "A" team in general. To keep her quiet, someone from the "A" team may have murdered her.

2. Who killed Ali: If Alison's (Sasha Pieterse) killer was cornered, who's to say they wouldn't murder again?

3. The NAT club's secrets: One theory about Ali's death is that she was murdered for knowing too much about the NAT club. If that's true, maybe Maya also found out about their illicit videos, and payed the same price.

4. Ali's alive: Ali being alive is one our our favorite theories. If Ali faked her own death — or if someone else forced her to — she (or whoever masterminded it) might be willing to do a lot to keep it a secret.

5. Ali has a twin: Alternatively, there's the theory that Ali has a twin who may still be alive and caught up in everything somehow. If so, that's another secret that someone may have killed to keep.

What do you think "Maya Knew" means? Let us know in the comments below!

Catch an all-new episode of PLL on Tuesday, July 31 at 8 p.m. ET/PT on ABC Family.

Rebecca Martin is an editor at Wetpaint Entertainment. Follow her on Twitter @BeccaMartin47.

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