Aria tries to process Spencer and Emily's news about Jason while dealing with her feelings for him; Hanna tries to be nice to her future stepsister Kate; 'A' turns up the heat on Emily by trying to push her to breaking point.

The liars finally reveal the torment "A" has put them through to the one person they trust outside their group, Dr. Anne Sullivan, but could she be next on "A's" target list?

All is not what it seems as "A" sends the girls on a hunt to destroy lives. Can the liars go through with their given tasks in order to save one, or will they ignore "A" to save those around them from being hurt?

It's the Halloween before Alison went missing and the friends hope to score an invite to Noel's Halloween party; Jenna challenges Ali for Queen Bee dominance; Aria learns a shocking revelation about Byron.

A month has passed since the liars were arrested and they're at each others' throats and Emily has been iced out completely. But what could have divided them so severely, has "A" finally won the game of divide and conquer?

The liars, realizing that "A" is not acting alone and their helper may be closer than they think, decide to enlist Caleb's hacking skills.

With Lucas missing and questions surrounding what happened out on the lake, Hanna can barely catch her breath; Spencer follows a lead about "A" which guides her to an unexpected place and revelation.

Toby continues to pursue Spencer, knowing that she is keeping something from him; Hanna begs the other girls to stop using Caleb to help with their search; Aria is desperate to save her relationship with Ezra.

After speaking to her friends about Caleb, Hanna feels they are giving her the cold shoulder; Emily hopes to re-introduce Maya to her mother.

Aria continues to question Holden on what exactly he is up to during their "date nights"; Hanna tries to figure out the latest situation with Kate; Emily gets help from an unlikely source to get back on the Rosewood swim team.

Hanna's worst nightmare comes to fruition when Caleb becomes a target of "A" and his computer is in possession of the cops; Aria learns what Holden's been keeping a secret.

A surprising new victim of "A" is revealed; Spencer runs from her family troubles right into Wren's arms; Ezra's new opportunity could push him away from Aria.