While Juliette tries her best to adjust to her new houseguest, Trubel makes herself at home and raids the fridge for some leftover Chinese food. She may be a rebel, but she knows a good thing when she sees it. Meanwhile, Nick needs to figure out how to handle the situation. He promises Juliette that, as soon as he gets his bearings on the Trubel situation, he'll try to make life easier for her.
Meanwhile, a group of affluent young women peruses the goods in a high-end clothing store on the other side of town. They may seem like random customers, but these women are actually a choreographed team of shoplifters. One of the women creates a diversion by knocking over a mannequin. When the store's staff is distracted by the commotion, the other women fill their bags with expensive clothes and swiftly exit the store. Unfortunately, one of the women is spotted by security. She manages to escape from the security guard, but she's now a wanted criminal.
Back at their hideout, the thieves are greeted by their caretaker. He's a Lebensauger, a leech-like Wesen who controls others through intimidation and manipulation. He's the brains of the operation, and he's corralled a group of down-and-out young girls to steal merchandise for him in exchange for food and shelter. He can't have a wanted criminal in his operation, so he quickly dispatches of the problem girl.
The next day, the girl's body is found in the woods. When Nick and Hank arrive to investigate (with an eager Trubel in tow), Wu notifies the detectives that the body has been completely drained of blood. This, along with the strange bite marks on the girl's body, suggests that a Wesen is to blame. But what type of Wesen leaves a bite mark like this? To the trailer!
Nick, Hank and Trubel sift through Aunt Marie's journals in search of a clue. Hank discovers a page of the book describing the Lebensauger, a leech-like Wesen that sucks the blood from its prey. The bite marks match perfectly. Moments later, Wu calls with some information on the victim: she's been in and out of shelters for several years, and she also has a number of shoplifting charges on her rap sheet.
Hank asks Wu to search for any recent shoplifting incidents. If she's a serial offender, the detectives may be able to establish a lead. Nick, Hank and Trubel head to the girl's group home in search of more information, but none of the girls can tell them anything. That is, until Trubel roughs up a young Wesen girl and obtains some valuable information. By now, it's become clear that Trubel is trouble. Nick will have to teach her the right and wrong paths to justice. She has the right instincts, though. The Grimm is strong in this one.
Following Trubel's lead, they stake out a local nighttime hotspot in search of a woman who recruits homeless girls for her shoplifting ring. They spot their potential target, but there's only one way to be certain: Trubel approaches the woman pretending to be the perfect target, and in a matter of minutes she's swept away to a secret warehouse. There she's greeted by the organization's other girls and their leader, the Lebensauger.
After dressing Trubel in a fancy disguise, they agree that she's the perfect addition for their team. When the Lebensauger reveals his Wesen form, he immediately discovers that Trubel is a Grimm. A fight ensues, and Nick and Hank arrive just in time to save Trubel from certain doom.
Trubel apologizes to Nick for her haphazard approach to detective work. If Nick will continue with her training, she promises to proceed with caution from here on out. Nick says he'll have to think about it, but he knows the answer: he loves having a Grimm partner around.
Meanwhile, Adalind searches through her mother's belongings and discovers a spell book. There's magic in this book that could solve all of her problems, but she'll need more ingredients to enact her plan...
Trubel continues her Grimm training with help from Monroe and Rosalee, but Nick can't keep her from diving into the action on his latest case.