Sometimes, when thinking and writing about Pretty Little Liars, it can be easy to get bogged down by what we don’t know, especially when it comes to the mysterious “A.” Is Ezra Uber “A”? Or is it someone else? We’re not sure! But we are relatively sure about who it isn’t. Here is a list of five characters we are (almost) positive will not be revealed as “A.”

Ella Montgomery

We’ve always doubted the possibility of Ella being “A” - she’s just too darn nice and obvious to be the omniscient antagonist but her recent trip to Vienna sealed the deal. We’re not sure how “A” manages to know and see all, as well as seemingly be everywhere at once, but we’re relatively sure she would have to be on this continent to pull this off. Sure, there’s a chance that Ella fabricated the entire trip to Austria, but Aria had to work too hard to get her mother to go for this whole thing to be a fake. Plus, who sics bees on herself? There’s commitment, and then there’s craziness.

The Liars

We actually think it would be kind of amazing if one of the Liars was, in fact, “A,” but we don’t think the show has the guts to pull this off. Go ahead, show, prove us wrong! Until then, we are going to move forward under the relatively safe assumption that one of the Liars isn’t harassing herself and her best friends. So, far PLL has done a pretty good job of keeping this mystery logical, but it would have to work really, really hard to convince us that there’s any logical explanation for one of the Liars being “A.” After all, every one of them have had near-death experiences at the presumed hands of “A.”

Ashley Marin

We do love Ashley Marin, but that’s not our reason for believing her incapable of being “A.” She is both too financially unstable and too ineffective at pulling off crime to be a master criminal. Ashley has absolutely no poker face. Remember the time she “borrowed” all of that money from one of her clients? She looked like she was about to faint at any given moment. And how about the time the police came to ask her to open up Wilden’s safety deposit box? She practically turned herself in for being at the scene of the crime the night of his murder. Nah, she doesn’t have the constitution for “A” or enough lasagna boxes of money to fund the operation.

Toby Cavanaugh

Toby has been a main “A” suspect more than once on PLL. In Season 1, the Liars were convinced that he was “A” (or at least killed Ali) and, in Season 3, we kind of were. Maybe this should make him a likely suspect, but it makes us majorly doubt his involvement. He has been a red herring too many times for us to believe he is actually “A.” Plus, he was completely distracted from the “A” game this season as he tried to figure out what happened with his mother. In fact, “A” had him wrapped around her finger, doing whatever she wanted in exchange for information about Marion Cavanaugh’s death. Toby is just too obvious to be “A.”

Caleb Rivers

We never would have entertained the idea of Caleb being “A” before (because it would have broken our Haleb hearts), but now that he’s heading off to star in Ravenswood, we’re nearly 100 percent positive that he is not our masked harasser. Caleb will have a whole other mystery in which to engage. Logistically, it just won’t work. Not to mention, Caleb has been one of the Liars’ chief tools in combating “A.” He has helped them follow cyber trails she left behind time and time again. He could be making it all up, but we don’t think so. The man did take a bullet for his girlfriend’s best friend (i.e. Emily). He’s pretty committed.

Do you agree with our list of “definitely not ‘A’s”? Why or why not? Is there anyone else you would add to the list? Sound off in the comments below!

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

Credit: Celebified Photo: Pretty Little Liars Halloween Special "grave New World" Preview Photos: Ezra Lurks In The Shadows While The Girls Search For Ali!