In the words of Golden Globe-winner Lena Dunham: Thank you Chad Lowe...for being so creepy! Ever since we learned during the Halloween episode that Aria's dear old dad met with Ali the night of her disappearance, he's been acting increasingly suspicious (and guilty). Byron tries smoothing things over with Aria, apologizing for believing she had anything to do with the shed fire that hurt Meredith, but Aria isn't exactly warming up to him.
Meanwhile, under the cover of darkness at Rosewood High, Spencer, Hanna and Emily are sneaking back into Creepy's Closet to retrieve Ali's diary—except all of his belongings are gone and the girls aren't alone. A hooded black figure runs out of the room, but no one get a good look at him/her. They spot the diary, or what they think is the diary, opening it to reveal a note from A: "Keep moving, ladies. Nothing to see here."
The next day, Mona runs into the girls at the cafe and tells them Harold bribed the janitor to let him takeover so he could stalk her, insinuating that he was the one to rig the fire at the 10k. Mona's parents found out and went to administration to turn him in. Of course, the liars don't believe any of it.
As it turns out, Hanna wasn't being honest when she said she didn't see who the hooded figure was. She knows it was Lucas, and confronts him. He's initially hesitant but admits to perpetrating the shed incident to stop Mona. Later, in the privacy of his house, he tells Hanna the full story: He's been selling test answers and Mona found out and has blackmailed him. And he was indeed the one on the skateboard that Toby almost mowed down (though Lucas thinks it was Mona). He's leaving Rosewood High for good to be homeschooled...and away from Mona. Somehow we don't think that will stop her.
Aria decides to do a bit of digging into her dad's alibi, and it's not as air-tight as she assumed. Byron and Ella spent the night in question knocking back glasses of red wine, which always makes Mrs. Montgomery sleep like the dead. Byron could have ostensibly sneaked out without her being the wiser. He continues to raise suspicions after he pilfers Ali's diary pages from Aria's boot. Meredith's onto him though, finding the pages in one of his drawers and returning it to Aria. She also admits to Aria that he came to see her the night of the incident and that he left her apartment to go meet up with Ali. Which officially makes Byron Suspect No. 1.
It's good Aria's found something of an ally in Meredith because Spencer, for one, is too busy facing off against Mona to be much help. You see, Mona decided to join Spence's Smarty Pants Club and is running against her for the position of captain. Thanks to a tie vote, it comes down to a quiz-off—one Spencer seems to be winning until she flubs the final question and Mona takes the title. After an SOS text from Spencer, Hanna comes to take her home, but not before chewing out Mona and cutting her off for good.
In Emilyland, she and Paige head to a swim team party to ease Paige's post-Halloween party anxiety, but Paige has some sort of PTSD flare-up and pulls over. Because what better way to alleviate fears than taking a meandering walk through the dark woods with only your girlfriend by your side? So it comes as little surprise that when the girls return to the car, they find the tire slashed and a black-hooded figure (Toby) retreating. Em and Paige make it back to town, and Paige sleeps over on an air mattress (really?) until her dad picks her up the next day.
The episode concludes with Mona tailing Byron at work—a turn of events that I don't entirely understand. But that's the beauty of "Pretty Little Liars," right?
What did you think of last night's episode? Do you think Lucas will be safe now that he's leaving Rosewood High? Did Byron kill Ali? Why is Meredith staying around? And what's up with Aria's mysterious illness? Tell us all your thoughts and theories in the comments below and on Twitter!