Credit: The CW

It’s an episode five years in the making: The Vampire Diaries 100th episode. We’ve been promised a lot from the much-anticipated installment, and we can’t wait to find out if it delivers. In the mean time, let’s review what we know about the Season 5, Episode 11 (“500 Years of Solitude”). Here’s a spoiler roundup for TVD’s 100th episode.

Katherine’s dying  probably. All signs point to the Big Bad Former Vamp biting it in the 100th episode. Not only is the episode named after her life, but we know from the promo and the episode synopsis that the fang gangers are anticipating her death. According to executive producer Julie Plec, “Death is knocking at the window in the 100th episode, but I’m not going to say if death is successful or with whom.” Will Katherine really die, or will it be someone else? As for the rest of the gang, well, they're all "bonding over hating Katherine (and by bonding, we mean drinking). 

A walk down memory lane. Whether or not Katherine does croak, we’ll be getting a walk down memory lane — mostly, her’s. In the synopsis, we learn that “Katherine remembers the traumatic night in 1490 when she gave birth to the daughter who was immediately taken from her” (see what a young Nadia will look like here), while the others “discuss some of Katherine’s most notorious moments.” Yikes! Katherine should have killed fewer people.

The return of some familiar faces. We’ve heard much talk about the return of cast members past — though, it’s unclear if they will be in these “notorious moments” flashbacks or in some other form. Confirmed for the docket: Aunt Jenna (Sara Canning) and Klaus Mikaelson (Joseph Morgan). But, here is a list of the five people we most want to see back, please and thank you.

Credit: The CW

Damon is pushing Elena away. In the midseason finale of TVD, Damon broke things off with Elena because he thought he was "bad" for her. And now Elena is struggling in the aftermath of the split. (Honestly, we're still trying to wrap our heads around this one, too, Elena.) In the extended promo for the milestone episode, Damon and Elena have yet another quarrel, but this one turns heated. “Stop acting like I’m perfect! I’ve done horrible things too,” Elena tells Damon, but then he totally freaks. “Stop defending me! I can’t change who I am, but I refuse to change you,” he screams. After waiting four seasons for Delena to get together, all this drama is breaking our hearts. Damon is headed down a downward spiral, and his old buddy Denzo isn’t going to make it easy on him.

Caroline “indulges in a little scandalous behavior” — with Klaus. We’re super intrigued by this tidbit from the episode synopsis, which implies that Caroline might be hooking up with someone. Now that we know Klaus will be making his return to Mystic Falls in the 100th episode — and that he definitely has an encounter with Caroline in the woods — it seems likely that the "scandalous behavior" involves the big bad hybrid. There’s also an Australian promo floating around the internet that shows Klaus and Caroline kissing (!), and more importantly, Caroline is the one initiating the kiss. So we know where this encounter is heading — and we couldn't be more than excited for Caroline's walk on the wild side! 

But will Caroline regret that decision? In the promo for "500 Days of Solitude," Caroline confesses to Elena: “I did a bad thing.” Is Caroline referring to her and Klaus's steamy kiss? Whether or not she regrets the kiss, however, is still TBD. 

The whole gang is gathered. What is everyone doing hanging in the Salvatore mansion as seen in these promo pics? Yes, waiting for Katherine to die, but is there more to it than that? And is this the big cast gathering we heard mention of at the 100th episode celebration, or does that include even more of the cast (members both past and present)?

Credit: The CW

Stefan will be there for Katherine. For all of us hoping for some Steferine love in the 100th episode, we might just get our wish. According to executive producer Caroline Dries, “[Katherine] doesn't have a huge fan base at the Salvatore mansion where she is, so Stefan is the person who's there for her.” Well, it isn’t confessions of their undying love or anything, but we’ll take what we can get.

Steferine’s hookup is coming out. It sounds like Elena will finally be getting wind of the Steferine hookup that went down just a few episodes past. According to the synopsis, “Caroline is mortified when she realizes she forgot to fill Elena in on the latest shocking gossip.” We’re guessing that “latest shocking gossip” has to be the steamy hook up between Stefan and Katherine that Caroline just happened to overhear.

Nadia has a plan to save her mother. We’re not ready to give up on Katherine yet — and neither is her daughter! According to the synopsis, “Nadia comes up with a frightening plan to protect her mother, and Stefan and Elena are forced to help her.” What could Nadia possibly be planning — is she still on the body-swapping thing? — and how would she force Stefan and Elena to help? What could she have over them? She has been spending a lot of time with Matt? And we’re still speculating that Nadia may be hiding something big.

Catch the next episode of The Vampire Diaries on Thursday, January 23, 2014 at 8 p.m. ET on the CW, followed by an all-new episode of Reign.

Kayti Burt is a contributing writer for Wetpaint Entertainment with a penchant for all things pop culture. Follow her on Twitter and Google+!