Pretty Little Liars isn't afraid to throw a crazy twist or ten our way, so we're always on the lookout for theories that can help us predict the next big OMG moment. That's why every Friday we like to delve into the world of fan theories and find an idea that's so out there, it might just have some merit.

This week, we want to talk about a theory we've seen floating around in a couple of places: that Toby Cavanaugh (Keegan Allen) was the masked person who shot Ezra at the end of the Season 4 finale.

Yes, this would be a huge twist, and it probably won't happen, since the show seems determined to keep Toby on the side of good. That said, there are some intriguing reasons to think this theory could be true, if the writers were willing to go in that direction.

Toby was MIA. Any time a character is MIA, was have to wonder if they're lying about their whereabouts. Also, the whole thing about Toby going to London and running into Melissa? It's weird, and awfully convenient. Could it be a lie?

Do we know that he stopped working with the "A" team? No, of course not, since it's impossible to know for sure that anyone on this show is actually a good guy. The fact that Toby was once linked to the dark side, even if he was probably doing it for good reasons, means we should always be a tad cautious about him.

Shadow Play. However, the bit of evidence we like best is linked to "Shadow Play," the noir episode. Not only did that episode generally highlight the trust issues between Spencer and Toby, but it also ended with Toby hitting Ezra, and warning the Liars "We don’t have much time, I hit him hard but I only hit him once." And then in the finale, Ezra was hit by the bullet... once. Hmm...

What do you think of this theory — is it possible, or totally crazy? Sound off in the comments below.

Catch the Pretty Little Liars Season 5 premiere on June 10, 2014 at 8 p.m. ET on ABC Family.