No one is more of a Grinch than Pretty Little Liars' 'A', and the mysterious murderer will bring chaos to Rosewood this Christmas.

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That doesn't mean Christmas cheer will be completely absent, however. It may only be September, but Pretty Little Liars fans can already watch Ezra (Ian Harding) and Aria (Lucy Hale) exchange holiday gifts in "How the 'A' Stole Christmas" (see video below)

Aria is looking for a low key Christmas, but Ezra has a different idea. Looking festive in a Santa hat, the teacher will give his girlfriend a pair of gorgeous earrings to go with whatever dress he's stowed away in a wrapped box. While Aria would prefer an 'Ali Decoder Ring' (wouldn't we all?), the teen seems quite pleased with the surprise present.

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Based on behind-the-scenes photos (see here) from the cast and crew, the Liars' caroling won't be the only festive part of their first Christmas special. From Nativity scenes to warm winter jackets, the residents of Rosewood look at least ready to take on the holidays if not 'A'.

Find out more when Pretty Little Liars joins ABC Family's '12 Days of Christmas' lineup.