With new key evidence in Alison's murder case, Hanna fears that "A" may be framing her after a visit from Det. Wilden. With paranoia setting in, Aria decides that she has to turn to Mona for answers if she is going to help Hanna. But is Aria ready to face her former tormentor, and more to the point, is Mona ready to give Aria the answers the PLLs are desperately looking for? Meanwhile, someone from Ali and Jason's past arrives in Rosewood and piques the girls' interest.