'Pretty Little Liars' Christmas Special Spoilers: 'A' Takes a Holiday; When Will the Episode Air?

ABC Family's "Pretty Little Liars," which has been on a hiatus after the first half of season 5 ended with Mona's death, will once again be back on air on Tuesday with its special Christmas-themed episode titled "When the A Stole Christmas."

The first half of the season ended on a grim note that saw Mona dying, and Spencer being arrested for the murder of Bethany Young. Tuesday's episode will pick up from the events of the fatal finale, and will see the Liars trying to gather evidence to clear Spencer's name.

At the end of season 5's midseason finale, the girls themselves were suspecting Alison to be A, and in the upcoming episode they will attempt to find out more about Alison's dark secrets, and establish a connection between Alison and Bethany. This is what prompted Aria, who initially said she would "rather dance on dead monkeys than go to Ali's stupid ice ball," to get dressed in her finest gown and attend Alison's Ice Ball.

A sneak peek of the episode also showed the girls receiving a snowball from 'A' with the message, "'A' takes a holiday. You should, too." Is 'A' really going to be missing in action in the Christmas-themed episode, or is it a ploy to get the girls to let their guards down?

Meanwhile, Alison will be battling her own fears, as Mona will be back in the form of a ghost. And even in death, Mona has a few surprises in store for Alison.

"The real surprises are the one she offers to Alison, who finally gets to see things through Mona's eyes," executive producer Marlene King revealed to TV Line. "She will offer us, through flashbacks, more insight into her life... and her death."

King also hinted that the "gift" that Mona left Hanna will be instrumental in clearing Spencer's name in the murder of Bethany Young. And although the murder charges won't go away by the end of the episode, "it meets its completion early on in 5B," King added.

Elaborating on why Mona would leave the gift to Hanna, King explained: "Well, even in their darkest moments, Hanna and Mona share a special bond. They've gone through so much together, and I think Hanna still has very sympathetic feelings for Mona. It makes sense that she'd be the one person Mona would reach out to."

The "Pretty Little Liars" 2014 Christmas episode will air on ABC Family on Tuesday, 9 December at 8 p.m. EST. The official synopsis reads: "Aria, Emily, Hanna and Spencer look to clear Spencer's name and prove a connection between Alison and Bethany, while Alison gets a glimpse at the past, present and future by a ghostly presence."