On Pretty Little Liars Season 3, Episode 10: “What Lies Beneath” Emily (Shay Mitchell) and Hanna (Ashley Benson) discovered a bag that belonged to Maya (Bianca Lawson) at the Kahn's cabin. In it they found a number of important items, including a knife with "LJ" carved into it.

But what does "LJ" mean? We assume it's someone’s initials, but whose? There's no obvious answer, and you know what that means: Speculation time! Here are our top four theories about who LJ is.

1. Lucas Gottesman (Brendan Robinson). Yes, it's "LJ" and not "LG," but maybe J is Lucas's middle initial. All we know is he seems to have been mixed up in the mystery somehow, and he's the only character we can think of with a "L" first name.

2. It's from Maya's stalker ex. The one she told Emily about, from her time in rehab. (Who we think might actually be Nate — hey, he could have a different real name!)

3. Maya had a secret identity. We know Alison (Sasha Pieterse) had at least one alias. Why couldn't Maya?

4. It's one of Ali's secret identities. Maybe Ali went by an LJ name sometimes. Or perhaps it's the initials of the name Ali's theoretical twin goes by. If Ali, or her twin, is alive and in hiding and Maya died because she found out about it (which is one possible theory), than perhaps the knife was part of the evidence she was collecting.

What do you think LJ stands for? Let us know in the comments below!

Catch an all-new episode of PLL on Tuesday, August 21 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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