'Pretty Little Liars': 4 Shocking Revelations From the Midseason Premiere

Pretty Little Liars: TV Still - 1/2/11 Fight - H
ABC Family

The second half of the sophomore season of Pretty Little Liars pulled out the stops -- and several key developments unfolded, including the reveal of a secret affair.

Here are four things that were unveiled during the episode:

[Warning: Spoilers ahead.]

1. Aria and Ezra's Romance Revealed: With Aria (Lucy Hale) and Ezra's (Ian Harding), her former English teacher, relationship outed the reactions to their romance weren't exactly what the two had hoped for. Now that Aria's parents, Ella (Holly Marie Combs) and Byron (Chad Lowe), are in the know and Aria's attempt at reassuring them that her love for Ezra is true turned out unsuccessful, the couple find themselves on the outside looking in. There could be some good: Ezra's ex Jackie now has a reason to depart, though Harding teased in August that she could still be around.

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2. The Gang Outsmarts "A": Aria and Ezra's confession wasn't the biggest development to stem from the action-packed episode, during which executive producer Marlene King and director Norman Buckley live tweeted. To gain an upper hand with anonymous troublemaker "A," Aria, Hanna (Ashley Benson), Spencer (Troian Bellisario) and Emily (Shay Mitchell) hatch a complicated plan that has everyone fooled. Serving out a community service sentence due in part to their supposed connection to Dr. Sullivan's (Annabeth Gish) sudden disappearance, the foursome are in what seems to be a heated fight, but it's discovered later on in the episode that it was all play. As a result, "A," falling for their risky plan, singles out Emily -- who is feeling the brunt of the pain -- in an attempt for a potential deal.

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3. Emily vs. "A": When Emily -- trying to rejoin the school swim team -- faces "A," she is the closest any member of the group has come to meeting the culprit, though s/he is conveniently hidden in the dark. At their meeting, it's there that Emily lays out the truth of the foursome's successful plan. Acting on emotion and becoming sloppy, "A" lunges for Emily, who is narrowly assaulted by a shovel. But the identity of "A" can't be revealed this soon, with s/he escaping before Aria, Spencer and Hanna can catch up and not before losing his/her cell phone.

4. Romances on the Rocks: As was teased in sneak peeks released by ABC Family, Hanna's love Caleb (Tyler Blackburn) returns, making this mightily awkward for Lucas (Brendan Robinson), who still harbors feelings for the blonde -- as evidenced by his threat to Caleb. As for Toby (Keegan Allen) and Spencer, things continued to go on a downward spiral, as she continued in her attempts for her ex-boyfriend to leave her alone, even when he tries to give her a homemade rocking chair.

For the most part, viewers were surprised by how much took place in the span of one hour. Wrote one viewer on Twitter: "Pretty Little Liars was crazy! Was not expecting so much of that. Aria/Ezra revealed, the girls messing with A, A's cell phone. Crazy." What had you talking?

Pretty Little Liars airs Mondays at 8 p.m. on ABC Family.