Nick and Juliette are both too nervous to eat dinner. Juliette now knows the world is more complicated than she could've ever imagined, but she still loves Nick. When Nick says he never stopped loving her, Juliette tells him to stop talking and the two passionately kiss. Elsewhere, Eric Renard has employed Baron Samedi to enact his "zombie" scheme on Portland, but he doesn't want the Captain to find out. The next night, Baron Samedi performs a voodoo ritual and sets his minions off on their destructive paths...
Monroe and Rosalee share a romantic dinner, and when Nick doesn't show up, they both hope that means things are going well with Juliette. Taking advantage of the privacy, Rosalee suggests they put off cleaning up until the morning, as she morphs for Monroe. Meanwhile, a castle spy calls Renard with information on the files he found in Eric's office. Off of this, Captain wonders what a "Thomas Schirach" is helping his brother with; on a trolley in Portland, a zombie rushes on board and attacks the trapped civilians.
In Vienna, Frau Pech has Adalind poisoned by a hotel bellman and extracts blood from her knocked out victim's body with a syringe. One must learn to be careful of the alliances one forges. Back in Portland, "zombies" are ravaging the city, but Nick and Juliette are completely unaware, lost in the bliss of long overdue love. It seems things between the two are finally back to normal, but a call from the precinct forces Nick, at least temporarily, away from Juliette.
Renard tells Nick about his brother's presence in town, and he doesn't think it's a good thing. Captain worries Eric might be in Portland for Nick's key and mentions his plan to dine with his brother later that night. Sgt. Wu barges in with an update on the riots breaking out downtown - it's quickly turning in to an "all-hands-on-deck" kind of thing. When Nick and Sgt. Wu arrive at Portland Coffee downtown, they realize the perps have done a number on the storefront. In the attic of the building, Sgt. Wu is bitten by Lilly O'Hara, who then jumps out a window after being chased by Nick. When Hank arrives, the two apprehend another zombie-like person and decide to take it into the Spice Shop for examining.
At the Spice Shop, Nick and Hank fill Monroe and Rosalee in on what's going on. After consulting some books, Rosalee thinks she's found the problem facing all these "zombie-like" people: voodoo-induced Wesen trances known as Dammerzustand. There are four stages to the trance, first being paralysis, followed by a drugged-like immobilization, then what seems to be death, before finally the last stage, which is basically a murderous rampage. There's a cure, but unfortunately the only time it's effective is during the final stage. Nick and Hank leave for the precinct as Rosalee prepares an antidote in a special three-pronged syringe.
Back at headquarters, Nick and Hank realize there have been 19 missing persons reports in the last 24 hours, which suggests a connection to the zombie riots downtown. They bring in an auto repair shop owner for questioning about his missing coworker, and get to hear the dispatch call made by Baron Samedi the day before; the call gives Nick and Hank a license plate and car to look out for. Back at the Spice Shop, the zombie wakes up before Rosalee finishes the antidote, and Monroe is forced to knock the guy out before he damages the entire shop. With the thing passed out, Rosalee rushes in and injects the remedy.
Back in Vienna, Frau Pech mixes Adalind's blood with a potion she made at home, and then consumes it. Suddenly, Frau Pech begins to morph into Adalind, while Adalind - passed out on the floor - begins to morph into Frau Pech. Within moments, the two have switched bodies, and Frau Pech examines her much younger physique in the mirror. Her plan worked. Suddenly, Stefania calls, intending to speak with the real Adalind, but Frau Pech answers instead. Stefania says she's found a way to deal with Frau Pech, and the new "Adalind" can't wait to hear...
Captain Renard meets with his brother Eric at the Heathman Hotel. Over dinner, Eric invited Renard back into the Royal Family - historic things are happening at the moment and he'd hate to see Captain cast further adrift. To ensure he's welcomed back, the Royals want Renard to get them Nick's key, and they're willing to give him a little more time. But Renard sees the blackmail clearly - either he gets them the key, or Eric will tell Nick everything about Captain's past. It's a catch-22, and he'll need more time deliberating.
Sgt. Wu brings Nick and Hank up to speed on Samedi's found car on the side of the road. The trunk is full of voodoo paraphernalia, and Nick can't fight the feeling that Baron's playing them all for fools. He was at the house where this all started, made an appearance on the hospital security cameras, and now left them a car full of voodoo materials. It all seems a little fishy. Hank has to get his cast taken off later that night, and encourages Nick to just have dinner with Juliette and take his mind off of things for a moment.
Nick meets back up with Juliette and tells her about his day. Nick says he's after a Cracher-Mortel - a Wesen that can spit something into people's faces that paralyzes them to the point where they appear dead. Then they wake up and act like zombies. It sounds absurd, but Juliette's determined to go along with it. Furthermore, she wants Nick to move back in; this is his house too and she doesn't want to be away from him any longer. Monroe calls Nick - the zombie woke up, and the potion worked. Nick and Juliette head for the Spice Shop.
Frau Pech - as Adalind - meets with Stefania. Stefania tells "Adalind" all about her plan to cross Frau Pech. To give the real Adalind her powers back, they need the still beating heart of a Hexenbiest. Stefania plans to lure Frau Pech into her tent and then have a henchman knock her out before extracting her heart. "Adalind" asks if she thinks that'll work, to which Stefania responds, "we're about to find out." Stefania was aware of Frau Pech's plan all along. Her henchman knocks "Adalind" out and Stefania stabs the now morphed Frau Pech in the heart. Elsewhere, Adalind awakes from her slumber, back in her original state. Ding-dong, the witch is dead...
The man in the Spice Shop - the former "zombie" - is the same man Baron Samedi attacked on the routine auto repair run. Nick asks the now normal mechanic about the man who attacked him, hopeful to get a lead on Samedi's whereabouts. Nick surmises the Baron's main hideout is the container yards from the intel given to him, and in private, tells Monroe and Rosalee about Renard's brother; Nick thinks they're after his key and gives the key to Rosalee to hide. With that taken care of, Juliette offers to help administer antidotes after Rosalee and Monroe cook up a larger quantity. Together, the group heads for the container yard...
At the shipping yard, Nick, Juliette, Rosalee and Monroe search for other victims, but Baron Samedi's walked them into a trap. Baron releases all of his "zombies" and the gang quickly releases they won't be able to administer shots to all of them, so they run for their lives. Seeing Samedi, Nick runs after the mastermind and chases him into a pitch-black shipping container, where the criminal disappears.
As Nick searches for Baron, he comes across a passport in a coffin, belonging to Thomas Schirach... except the picture is of Nick! Turning around, Nick is attacked by Baron Samedi and turned into a "zombie." Eric Renard emerges from the shadows and helps place Nick into the coffin. He's got what he came for, and they have a long flight ahead. Outside, Rosalee, Monroe and Juliette wait for Nick in the car, but he doesn't show up. As the "zombies" attack from all sides, they're starting to run out of options...
As Juliette begins to fully embrace Nick's life as a Grimm, Eric Renard's undead plot threatens to bring all of Portland to a panicked halt. Meanwhile, Adalind makes a desperate push to get her powers back.