A case of breaking and entering introduces Nick and Hank to a mysterious family whose cultural background blurs the line of right and wrong. Meanwhile, Nick tasks Monroe with safeguarding Aunt Marie.

Highly respected judge Logan Patterson is murdered, and shortly after several other people who played some part in the conviction and incarceration of an escaped giant of unnatural strength. Nick is badly wounded, out of action. Monroe however shows unusual enthusiasm to help out while Hank follows the paper trail.

Monroe's potion finally relieves Renard and Juliette's passionate obsession, so he and Nick can collaborate again, even closer then ever, with Monroe and Hank aboard, against the royal conspirators. Three youngster Wesen, Cole Pritchard, his girl Krystal Fletcher and his former cell-mate Gus, repeatedly commit robberies using their Wesen appearances as if masks. Monroe witnessed a bank robbery and alerts Nick's police team as well as the 'Wesen Council', as this is a blatant violation of the centuries old Schwaben code, which Amsterdam HQ chief De Groot orders enforced. Juliette has novel supernatural experiences at home.

Nick is back on lovers' terms with Juliette, who remains eager to learn about ferals. Nick must however give priority to the violent crime wave caused by zombies. As he feared, they are created by the voodoo 'baron', who sets a trap as instructed. Captain Sean Renard informs Nick about his mistrusting meeting with visiting European royal half-brother Eric and the counterfeit documents Eric had prepared at the castle. Still in Vienna, Adalind, poisoned by Pech to switch appearances, is seen roughly overtaken by the gypsy witch's family Popescu. Rosalee prepares a zombie antidote, but once tracked down in the port, the superior zombie numbers corner down Nick's party.

Monroe (Silas Weir Mitchell) fights an impossible battle to convince his parents (guest stars Dee Wallace and Chris Mulkey) to embrace the life choices he's made. Meanwhile, Nick (David Giuntoli) turns to Juliette (Bitsie Tulloch) to help him figure out the Wesen aspect of his cop-killing scalper investigation. On the Royal Baby front, Captain Renard (Sasha Roiz) learns new information that forces him to contact Adalind (Claire Coffee) in the interest of keeping her and the baby safe from Viktor (guest star Alexis Denisof).

The Verrat find out that Adelind and her baby have gone to Captain Sean Renard for help. Nick enlists the help of Monroe and Rosalee to keep Adalind safe, as his mother figures how to deal with the Royals.

The Wesenrein act on their many threats against Monroe and Rosalee's marriage. Meanwhile, Nick and Hank bring Wu to a place where he's sure to find the answers he's looking for. Elsewhere, Juliette tries to come to grips with her new reality.

After Monroe's (Silas Weir Mitchell) abduction by the Wesenrein, Nick (David Giuntoli) gathers the whole team, including Wu (Reggie Lee), to track him down and return him to Rosalee (Bree Turner). As the search intensifies, Juliette (Bitsie Tulloch) learns more about her new reality as a Hexenbiest.

A beauty regimen proves deadly for a young woman, who seems to have aged 70 years when Nick and Hank find her lifeless body. As they search for proof of Wesen involvement, they are led to a local doctor, and end up enlisting Rosalee's help in their investigation. Meanwhile, Eve takes a bold step to learn more about Capt. Renard's nefarious dealings.