The mysterious A's identity was revealed during Pretty Little Liars' explosive March finale, but it's left the girls of Rosewood with more questions than answers.

In a sneak peek from Tuesday's episode, Hanna Marin (Ashley Benson, 22) visits A -- a.k.a. her former BFF, Mona Vanderwaal (Janel Paris, 23) -- in a psychiatric hospital.

"We still haven't seen any changes, but I'm sure she appreciates your visits," a nurse tells Hanna, presumably unaware that Mona had been tormenting her pals for years.

To her own surprise, Hanna's presence goes unnoticed, as Mona continues to gaze off in the distance, never uttering a word.

"Your friend is here," the nurse informs a despondent Mona. "Can you say hello?"

The third season of Pretty Little Liars premieres June 5 at 8 p.m. EST on ABC Family.