Who Is A?: 'Pretty Little Liars' Cast Teases Season 2 Finale On 'Good Morning America' (VIDEO)

For two seasons, fans of ABC Family's "Pretty Little Liars" have been dying to know one thing: Who Is A?

The text messaging extortionist has been haunting Aria (Lucy Hale), Hanna (Ashley Benson), Spencer (Troian Bellisario) and Emily (Shay Mitchell) and on the Season 2 finale (Mon., March 19, 8 p.m. ET on ABC Family), A's identity will finally be revealed.

Three of the "Pretty Little Lairs" -- Lucy Hale, Troian Bellasario and Shay Mitchell -- teased fans at "Good Morning America" (weekdays on ABC) about who the mystery texter could be, each offering a clue:

• A loathes one of the "Pretty Little Liars" more than the others, Hale said.
• A has a motive to justify A's evil deeds, Emily added.
• A admires one of the "Pretty Little Liars" more than the others, Bellisario explained.

Though many possibilities have been floating around -- nerd-turned-queen bee Mona, Spencer's sister Melissa, the no-longer-blind Jenna and the rest of the cast of mysterious characters in the fictional Rosewood, PA -- the young fans gathered in New York City's Times Square to offer their two cents.

Based on the "Liars'" clues above, many fans believed Spencer was A. "I think it's one of the coolest possibilities that Spencer could be torturing even herself," said Bellisario, who plays the tightly-wound Spencer. "Like she's so warped and twisted [that she could be A]."

But is it out of the question? "I think it's totally possible," she added.

And good news for "Pretty Little Liars" fans: Season 3 is only a few months away. ABC Family just announced the series will be back on June 5.

Find out who A really is on the "Pretty Little Liars" Season 2 finale on Mon., March 19 at 8 p.m. ET on ABC Family.

TV Replay scours the vast television landscape to find the most interesting, amusing, and, on a good day, amazing moments, and delivers them right to your browser.