If there's one thing that you can say about Pretty Little Liars, it's that there's not a functional family in the bunch. That's why it almost didn't shock me that Charles is Big A and a relative of the DiLaurentis family. Of course ultimate A would be a member of the DiLaurentis clan — given the way Mrs. DiLaurentis' parenting had Ali and Jason turn out, I'm not at all surprised that another one of her family members would become an obsessive, psychotic stalker. But while the DiLaurentis' are plenty messed up, Ali's family might not be the only one attached to Charles. Spencer could be related to Charles too, and the show suggests that Spencer might know exactly who he is.
In the Season 6 premiere "Game On Charles," Spencer tells the girls that she had a very close run-in with the person who has made their lives hell over the course of two years. She tells them that something was very familiar about Charles, almost like a someone you haven't seen in years, like a cousin you knew when you were really little. I think it's particularly telling that Spencer had this encounter and got this vibe from Charles — even if all of the girls know Charles in some capacity, Spencer could know him best due to the connection between Mr. Hastings and Mrs. DiLaurentis. Knowing Spencer intimately at one point in her life is a major clue to A's identity, and here's who might fit the bill:
Okay, yes, technically Garrett isn't so much "alive" as "not alive." But if you've watched Bustle's brilliant TV editor Sam's video on why Garrett could be Charles (and, obviously, not dead) you might be sold, too. The thing that had my own brain whirling about the Garrett thing recently was the fact that Garrett made it a point to tell Spencer that she was his favorite, and she was the one that he wanted to keep safe the most. Could that be a hint that maybe Garrett is Charles with two different personalities? Maybe when "Garrett" "died," Charles could come out and play for real.
Ahh, yes — Mr. Kingston. He's been a top A suspect for a while, and there's a very real chance that he could be the guy under the Charles mask. (After all, "I was in England!" can't be an excuse for everything.) Perhaps Spencer knew Wren when he was a child and then re-met him when Melissa began dating him, which is what sparked their initial attraction. Would that mean that Spencer might have dated her tormentor?? Yes, and it's way too "ew" to think about. Still: not counting Wren out of this fight.
Spencer didn't spend too much time with Lucas over the years, but they definitely know each other. It can't be a coincidence that Charles DiLaurentis is an anagram for "Nerd Lucas Is The Liar," or a red herring that Lucas loathes Ali and everything she stands for. Could Spencer's brief interactions with Lucas have been enough for her to say that she recognized his mannerisms?
A Total Rando
Like, say, Harold Crane from the Lost Woods Resort. Spencer met Harold and talked to him, so she'd definitely know who he was. Plus, if Spencer was vibing off some past memories of Charles, she might not have even realized that Harold and Charles had similar tendencies — being trapped in a dollhouse does make you question everything.
Whoever is under Charles' mask, it's someone Spencer knows — and the reveal will change everything.