Friday's episode of The Originals will feature a very special return, just in time to help the Mikaelsons finally get an edge on their new big bad -- The Hollow.

Davina (Danielle Campbell) will be the savior that Klaus (Joseph Morgan) and Hayley (Phoebe Tonkin) need to stop the determined witch ghost from taking their daughter Hope (Summer Fontana). Considering Freya (Riley Voelkel) sacrificed Davina to the Ancestors in order to save Klaus last season, it's an ironic twist that the young witch will now be the one to save all of New Orleans from this terrifying new threat.

In this week's episode, Davina -- or more accurately the spirit of Davina -- will convene with Klaus and Hayley to give them The Hollow's backstory... And hopefully the information they need to finally get a leg up on the ghost that has bested them at every step this season. TVGuide.com talked Danielle Campbell about Davina's return, going face to face with Klaus and why Hayley is the key to defeating The Hollow.

Davina is going to come face to face with Klaus. What can you say about that reunion, and what does she have to say to him after what happened last season?

Danielle Campbell: Davina wants to protect the people she cares about. So in this episode she's really trying to make sure that she gives them the best advantage that she can with The Hollow. She needs to advise them and give the backstory of The Hollow in order for them to defeat her.

Davina has this new role as a sort of gatekeeper to the Ancestors, but the last we saw of Davina, the Ancestors were trying to tear her soul to shreds. What can you say about her relationship with them and how it got to this point?

Campbell: She obviously has passed. She can't come back at this point. They've gotten rid of the people that really hurt her so now she's in a space where she can just watch over the people that she cares about. She's not at risk of harm anymore.

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Davina knows a lot more about The Hollow than everyone in New Orleans. What can you tease about why The Hollow is such a threatening enemy?

Campbell: Davina had so much power because she was one of the Harvest girls, one of the kids that were born with an immense amount of power. The Hollow as one of the first witches is one of those as well. She was such a dark soul, her magic is very dark as well. The only thing that The Hollow wants to do is to harm everyone and anyone that she can in her past. Davina, with all the people that she loves in New Orleans, she wants to give everyone as much advantage against The Hollow as she can.

We know that Hayley is going to be the key to stopping The Hollow. What can you tease about why Hayley is so important?

Campbell: Davina really needed to talk to Hayley to describe The Hollow's backstory so that she can give Hayley the tools she needs in order to defeat The Hollow.

At the end of last week's episode, Josh has this really hopeful look on his face when he finds out that Vincent can feel Davina. Can we read into that and hope Josh can come up with a way to bring her back for real?

Campbell: I think he's always going to hope he can bring her back. I think he lost a person that the really cares about and more than anything he just wants to see her again.

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What was your favorite part of getting to return to the show?

Campbell: Getting to see everyone again! I get to see the cast when they are out in LA but that's never for too long, so it was nice to be able to see them all in Atlanta and get to see our crew as well. It's so nice being able to see everyone in one space.

Is there any moment in the episode that you are most excited for fans to see?

Campbell: It's one of her reunions! I will say that.

The Originals airs Fridays at 8/7c on The CW.

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