Pretty Little Liars Season 5 spoilers: Will the liars prove Spencer innocent and Alison guilty?

Pretty Little Liars Season 5 will return with the rest of the episodes in January and fans are eager to know more about Spencer's fate as she has been charged for Bethany's murder.

Show creator Marlene King said that Mona's friend will enter when season 5B premieres. Lesley was the one with whom Mona was talking to before getting killed. Her friend is now in Rosewood to find the real murderer.

"In the episode where Mona met her demise, she was talking to her friend Lesley on the phone that day and we finally get to meet Lesley," King told E Online. "She comes to town."

However, it is not yet clear if Lesley will befriend the liars or take Ali's side.

The liars, Spencer, Aria, Hanna and Emily, meanwhile have decided to spend their Christmas collecting proof of their friend's innocence as they strongly believe that it is the handiwork of Alison.

As of now, they know that Mona learned about Mrs DiLaurentis' affair with Bethany's father. And that Ali knew everything about it and was jealous of Bethany.

Mona's investigation further revealed that it was Ali who tempted Bethany to come to Rosewood, most probably to get rid of her.

Now it is up to the liars to find concrete proof to use against their former BFF and free Spencer from the wrong allegations.

The official synopsis for the mid-season premiere episode titled Through a Glass, Darkly reads:

Three months have passed, and Mona's friends and family are still mourning their loss and more adamant than ever that Alison had something to do with Mona's death. Ready to put "A's" game to an end and get justice for Mona, the PLLs ramp up their search for evidence that could prove Alison killed Mona. But with Alison claiming her innocence and having a seemingly airtight alibi, the Liars may have to resort to more shady tactics to put Ali away.

Meanwhile, Emily and Paige reach a crossroad in their relationship, and Aria starts to worry about her future.

Pretty Little Liars Season 5B will premiere on 6 January on ABC Family.