In this sneak peek from the Pretty Little Liars Season 4 Halloween special, we see Hanna (Ashley Benson) wandering the crypts of Ravenswood alone. Well, at least she thinks she’s alone. She seems to have been separated from the other Liars and is trying to find her way out of the maze, but is completely unaware of the person following her, aka a mysterious figure in a World War I soldier’s costume complete with gas mask to keep his (or her) identity a mystery. Who might Hanna’s follower be? We speculate below.

Ezra

Credit: ABC Family

Ezra (Ian Harding) is the obvious guess in the scenario. He appears to be revealed as “A” in the summer finale, and “A” has a sketch of the World War I uniform as a costume idea on one of his many lair displays. We also see someone, presumably Ezra, getting into the costume at the very end of the summer finale. Finally, we have seen glimpses of Ezra in the outfit in promo pics and videos for the Halloween episode. Basically, many roads lead to Ezra as the creepy World War II soldier.

Luke

Credit: ABC Family

Of course, if photo evidence can be trusted, we have also seen Ravenswood main cast member Luke (Brett Dier) in the World War I get-up. Much of the Ravenswood crew will be introduced in the PLL Halloween special, but we’re not sure what role Luke will play. Perhaps he is wandering the Ravenswood crypts in an effort to get away from the town gossip (his father was recently murdered and his mother is the chief suspect). Though the person following Hanna in the clip seems nefarious, it could just be our Creeper Radar is a little sensitive given past Halloween specials. We could get behind a scene with Hanna and Luke in which the two bond over having parents on trial for murder.

Alison

Who says only tall, dashing men can dress up as World War I soldiers? We think petite blonde Alison (Sasha Pieterse) could totally pull off the look! The Liars are at the Ravenswood Founder Party to find their allegedly deceased bestie, but she doesn’t want to be found - at least not by “A,” who seems to be hot on the Liars’ trails. Did Ali come dressed to the party not only in a costume that keeps her identity a secret, but one worn by at least two other party attendants? Kind of a fashion faux pas, but with one’s life on the line, one cannot be too careful.

Who do you think is following Hanna? Share your theories in the comments below!

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