Pretty Little Liars Season 4 Episode 20 Free Fall
Spencer wakes up in her pjs sitting in Mr Fitz's desk reading Allison's journal. Fitz enter the classroom and ask if she's been there all night. He says that the path she's been going down is very dangerous.
Ezra tells Aria about Spencer before the girls have a chance to tell her that Ezra is A.They give Spencer an intervention about her drug use.
The girls hatch a plan to prove Ezra is A by going to his and Ali's meeting place in the zoo. He goes to the cabin to look for Arial instead.
Aria finds a book Ezra was writing about Ali. She runs into the woods when she sees him coming. Turns out he knew who she was the whole time. He only stopped writing when they fell in love but started up again when they broke up.