Ready to unearth some sec rets, “Pretty Little Liars” fans? Hanna, Spencer, Aria and Emily want answers in the mystery of Ali and “A,” and when the ABC Family series returns they’ll be chasing every lead they got.

Season 4B of “Pretty Little Liars” will premiere on Tuesday, Jan. 7 with “Who’s In The Box.” As we previously reported, the midseason premiere will find the four girls looking into who might really be buried in Alison’s grave. And while Hanna appears to have a lead on who the body might belong to, she’ll share a bigger secret with her friends in the following episode, “Love ShAck Baby.”

According to a leaked synopsis for episode 15, Hanna will reveal to the others that she has Alison’s diary. “The girls hope it can shed light on their many questions,” teases the press release from ABC Family. But the diary sounds too good to be true – because the truth inside can’t be uncovered until the code its written in can be cracked.  

It’ll be up to each of the girls as they take turns trying to figure out “which stories are about them.” However each story will get more personal … meaning that Hanna, Spencer, Aria and Emily won’t want to admit which tale involves them.

With the stakes raised, the diary can reveal who’s been chasing after Alison the past couple of years. But the girls must face their own hidden secrets first before they’re able to help Ali.

The coded diary won’t be the only jaw-dropper in episode 15. “Pretty Little Liars” fans can also look forward to Spencer catching her father interacting with Alison’s mom, Mrs. DiLaurentis. Needless to say – Spencer is suspicious!

What do you think will happen in episode 15 of “Pretty Little Liars”? Let us know your thought in the comments section or send a tweet to @AmandaTVScoop.

“Pretty Little Liars” returns to ABC Family on Tuesday, Jan. 7 at 8 p.m.