Elena is back in tonight’s all new episode of The Vampire Diaries, so everything is back to normal, right? Wrong! There are werewolf venom-induced hallucinations, doppelganger updates, and awkward truth-tellings. Basically, it’s one big TVD shake-up. Here’s everything we know about Season 5, Episode 16 (“While You Were Sleeping”).

Elena still doesn’t know the truth about Damon, but she will

Elena’s back in her body in tonight’s episode, but she still doesn’t know about all of the murdering Damon did while she was banished from her body by Katherine. In this sneak peek, we see Jeremy and Matt taunt Damon about how she will react when she learned the truth. He threatens them to keep quiet — he wants to be the one to tell her. And we think he will, judging by this line from the synopsis: “Damon finally tells Elena the truth about his recent activities, and they come to a new agreement about their relationship.”

Elena’s having dangerous hallucinations

But, for most of the episode, it sounds like Elena will be distracted by some epic hallucinations that will cause her to go “a bit nutso.” They may also put Damon in danger. Now that she’s been infected with the werewolf-laced Ripper Virus, Elena’s bite is probably lethal to other vampires, but all Elena wants to do is make out with Damon. #VampireProblems, amirite?

There will be Delena “sexy time”

And what Elena wants, Elena gets. According to Ian Somerhalder (via TVLine), “There’s some sexy time happening. Exes, man. What are you going to do?” Totally. Apparently, this is a continuation of the scene we see in the promo in which Damon tells Elena to stop loving him, and she yells back at him that she can’t. Then, passionate embracing ensues.

Caroline uncovers a “frightening secret”

Meanwhile, Caroline is conducting some sleuthing into Dr. Wes’ research. According to the synopsis, while going through Dr. Wes’ files, she “discovers a frightening secret.” Uh oh. Are there more Ripper Vampires out there, ready to cull the vampire population via cannibalism? Or something.

Enzo is back!

Praise the TV gods, Enzo is back in tonight’s episode, and he’s surprisingly teaming up with Caroline. According to the synopsis, he runs into Caroline when she is ransacking Dr. Wes’ stuff, “claiming to have the solution everyone is searching for.” As seen in the promo, Caroline and Enzo meet up with Stefan at a train yard, but they’re not alone.

The Travelers love doppelgangers

Stefan, Caroline, and Enzo “are joined by a group of Travelers,” including Sloan, the sexy Traveler mouthpiece who made the deal with Dr. Wes to finance his research. In tonight’s episode, she “reveals new information on the importance of doppelgangers.” Great, more doppelganger mythology!

Meet Elena’s friend Luke

Tonight marks the introduction of a new character: Luke. According to the synopsis, “During spring break on a mostly deserted Whitmore campus, Elena runs into Luke, a student who seems to know her, though she has no memory of meeting him.” Did he and Katherine hang out? Sounds random, but she had to pretend to be in college some of the time, right?

Luke may be Liv’s brother

We know that Luke has a sister on campus he will do anything to protect — and the synopsis for tonight’s episode tells us: “Recently dumped by his boyfriend, Luke proposes that he and Elena spend the break getting drunk together, but she sends him off on an urgent mission to find Bonnie and the ‘newbie’ witch, Liv.” Is Liv the sister he’s trying to protect?

Witch mentor time

Speaking of Bonnie and Liv, they’re totally friends now. In this sneak peek, Bonnie is testing Liv’s magical abilities with a simple fire spell and checking her ego — at the same time! Yeah, she’s a pretty good multi-tasker (totally a prerequisite for any anchor worth her salt).

Catch this episode of The Vampire Diaries on Thursday, March 20 at 8 p.m. ET on The CW.

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