Tonight’s episode of The Vampire Diaries is the last before we break for the holidays, and the show won’t return until 2013! Get some last-minute teasers from the stars.

“O Come, All Ye Faithful” promises to both be dramatic and vaguely Christmas-esque. But it’s serious business in Mystic Falls, and Joseph Morgan (Klaus) warns TV Guide that there’ll be serious repercussions for Tyler when Klaus finds out what he’s doing.

Klaus, “Will be utterly furious,” Morgan says. “We’ve seen some of what Klaus is capable of, but he’s going to go very far when this comes to a conclusion. He won’t take that lightly.”

As Michael Trevino (Tyler) says, “nothing ever goes according to plan, something always goes wrong in the middle, and you have to adapt.” And in “O Come, All Ye Faithful,” that’s exactly what he will have to do: “it’s a huge episode for Tyler,” the actor teases. “It’s time to … take charge and with that comes some consequences.”

Klaus, meanwhile, will also be busy moving in on Tyler’s girl. Morgan says that while Caroline is still playing him, “she’s starting to understand him a little more. [He’s] opening up to her in that way, laying himself on the line and just being a little more charming and less threatening and aggressive.”

Candice Accola (Caroline) adds to this when speaking to IGN, saying, “Klaus is just enchanted with her. He also knows she’s playing him, but I think he likes that she’s playing him because he’s still a step ahead of her.” But Accola insists that, “she’s definitely involved, but she still has an arm’s length between them. She’s definitely not on his side.”

While Accola is definitely not Team Carolaus, she does see the appeal of their relationship. “For a character like Klaus, he’s so dark, but he starts to become genuine and show humanity” with Caroline, she explains. “He just loves her, and it’s that simple. It’s like she saved him and is bringing humanity into his life, which is so romantic – but so not healthy and not realistic!”

The Vampire Diaries 4×09 “O Come, All Ye Faithful” airs tonight at 8/7c on The CW.