While Ezra was helping Aria pack to elope, the FBI comes to the apartment and reveals that they have reason to believe that Ezra’s ex-girlfriend is still alive.
The episode ends with Ali, Emily, Hanna and Spencer finding the old storm cellar that Mary spoke about. They discover that Jessica was using it as her lair.
Apparently, Jessica knew that Ali got out of her grave when she buried her. She was investigating everyone in town when they noticed that a file on Aria is missing.
When they checked Mary’s files, it reveals that Mary had a second child. It wasn’t mentioned if the baby was a boy or a girl, but the papers state that Mary did not have any complications with her second child.
It also shows that whoever Mary’s second child is, he or she is the same age as the Liars. The alarm in Spencer’s car goes off right outside the lair.
Once they were all inside the car, a countdown begins. They thought that the car is going to blow up but instead, a message pops up saying that they will die if they don’t find out who Charlotte’s killer is before the sender does.
Jessica’s lair then blows up and Hanna watches a mysterious person write ‘I see you’ on the back window of the car. When the stalker returns to the lair, he or she throws Aria’s file on a desk and burn Noel’s file.
Fans now suspect Noel to be Mary’s second child. Some fans are positive that he’s got something to do with Yvonne’s assault and is probably the person who blew up Jessica’s lair.