The Vampire Diaries The Vampire Diaries

The Vampire Diaries' Jenna Sommers remains clueless about Mystic Falls' supernatural inhabitants. But as we saw last week, she may be catching on.

"She started having these inklings and mistrust creeping in largely due to what John has been mumbling," says Sara Canning. "Jenna is straight up with Alaric and says, 'If this is going to work you need to be honest with me' and he really doesn't have anything to say."

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That moment of silence from Jenna's boyfriend, Alaric, played by Matt Davis, was the last scene between the couple in the most recent episode, and Canning admits, "It's very uncertain if the relationship is going to completely crumble."

On Thursday's episode, Alaric finally will confess to Jenna. But what will he divulge? Let's just say she won't find out niece Elena is dating a vampire anytime soon.

"The confession is linked to what is more pressing on Jenna ... she's obviously not asking about his vampire-fighting extracurricular activities," says the actress.

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Jenna previously thought Alaric had a dead ex-wife named Isobel, but John has been pushing her to probe Alaric about the subject.

"She thinks she's dead. When John is saying, 'Did they find her body?' it bothers her, but a large part of her is like, this is what he does — he comes back to town and stirs up stuff just to stir it up," Canning says. "I think it's a definite discomfort, but I don't know that she's imagined what it would be like to meet Isobel or be told she's alive."

If Jenna only knew Isobel was not only alive, but a vampire who's Elena's biological mother.

Canning says her character has grown as a parental guardian and as a person making smarter choices, so she's excited about what lies ahead:

"In the next few episodes we're going to see something happen that is really going to rock her world and have her question if she is in such a steady and stable spot as she thought she was."

Do you want her to learn the truth or is ignorance bliss?

The Vampire Diaries airs Thursdays at 8/7c on CW.

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