In the world of Pretty Little Liars, there's no idea that's too crazy to potentially be true, which is why we like to dive into the world of fantastic fan theories every week to bring you concepts that are totally out there, but are just so interesting, they might even be right!

This week, we want to turn your attention to the night Ali "died." More specifically, the moment when a nearly passed-out Jason saw Melissa and CeCe talking — or did he? We're intrigued by the theory posed by this Tumblr user that Jason didn't actually see CeCe at all — he saw none other than his little sis!

If you recall, Jason was super duper crazy drunk (and high!) the night Ali disappeared. Like, blackout drunk.

However, at one point he did manage to make it outside, where he saw Melissa talking to a blonde who was wearing the same clothing as Ali. He thought it was his sister, but when he called her name the blonde turned at it was actually CeCe.

Is it possible that Jason really did see his little sis, and not CeCe? As the clever Tumblr theorizer points out, Ali and CeCe look a lot alike, and in Jason's mind-altered state, it's possible he got it wrong. The writers have said that flashbacks are tied to characters' POVs, so if they remember wrong, the flashback will be wrong. If Jason was off on this point, it would throw the entire timeline of Ali's last night into question.

What do you think of this theory — completely crazy, or potentially true? Do you like the idea, or is it too wacky? Sound off in the comments below!

Find Pretty Little Liars spoilers here.

Catch the Pretty Little Liars Season 4 Halloween special on Tuesday, October 22, 2013 at 8 p.m. ET on ABC Family.

Rebecca Martin is an Associate Editor at Wetpaint Entertainment and our resident Game of Thrones, Breaking Bad, and genre TV expert. Follow her on Twitter and Google+!