I thought of making myself a beautiful wooden marionette. It must be wonderful, one that can dance, fence, and turn somersaults.
At the academic decathlon trials, students are playing against each other and one student, Pierce Higgins, clearly does better than the others. He misses one question and glares at Jenny Lee, the student who does answer it, while his mother, Dr. Higgins, watches from the audience.
Juliette comes down and asks Nick to help her zip up her dress. As he does, Nick says that she's wearing the perfume that he bought her for Christmas. He thanks her for coming to the award ceremony in honor of Renard. Juliette hesitates briefly when Nick mentions Renard's name.
After the decathlon trials, the teacher assures everyone that they're doing well. The rest of the team plans to go out and Dr. Higgins reluctantly lets Pierce go with them and they go to a local diner. The others point out that Pierce has an advantage because his mother is an award-winning scientist. His classmates notice that Pierce isn't eating and encourage him to eat some fries. After a moment, Pierce does and then they wish each other well and share a toast.
After they're done, the students go their separate ways and Pierce's friend Brandon Kingston walks through the park. He hears something moving in the surrounding trees and hesitates, and a Wesen leaps out and attacks him.
At the award ceremony, Renard speaks in honor of the Landmark Organization that is giving him the award. Juliette watches him intently and Renard notices as he wraps up his speech. Afterward, Nick, Hank, and Wu offer their congratulations. While Nick takes a call, Renard asks Juliette if she's feeling better and she says that she is. Nick tells them that they have to take a call. Since Hank took a cab, Nick has to take the car so Renard offers to drop Juliette off. Hank leaves Juliette with her drink and she sips heavily from it.
Hank and Nick go to the park and Franco informs them that someone attacked Brandon, apparently with a hunting knife, and partially severed his head from his body. There's no sign of theft and Nick works out where he was attacked and then dragged out of sight. They hear Brandon's phone ringing from nearby and Nick answers it, and one of his friends, Jenny, asks where Brandon is.
Renard drops Juliette off at her home and he watches her go inside. Once she is inside, Juliette goes upstairs to her bedroom and undresses. Meanwhile, Renard takes the spare key from the porch and enters the house, and hears Juliette showering upstairs. He goes up and watches Juliette from the bathroom door. As he turns, he sees a photo of Nick and Juliette, picks it up to examine it, and drops it. Juliette hears the glass break and assumes that Nick is in the house. When she goes out, she discovers that the glass covering the photograph is broken. Outside, Renard speeds away, his face shifting. He goes up on the curb and grounds to a halt, narrowly missing a pedestrian. The man assumes that he's drunk and asks for his keys, and Renard partially transforms and punches him unconscious. The captain then gets back in the car and drives off.
The next day, Nick and Hank meet at the Higgins home and talk to three of the students, Pierce, Stan, and Jenny. Kevin is too upset to come over. They describe what happen and Mrs. Higgins explains that whichever one of them wins represents the school at nationals. Jenny blames herself since she offered them rides but Brandon walked home separately. They insist that no one hated Brandon. Jenny explains that she called Brandon because she just wanted to talk and they weren't romantically involved. As they leave, Nick says that he doesn't believe any of them were Wesen. Outside, Don Anker, the decathlon coach, arrives and demands to know what they've found out. Anker loses his temper and Nick sees him as a Lowen, and Hank notices his partner react. The teacher tells them that he was alone the previous night and goes inside to comfort the students, while Nick confirms for Hank that Anker is a Wesen.
Back at the station, the detectives confirm that Anker has a record of losing his temper but no seriously record. They report to Renard, who warns them to be careful about destroying a man's reputation. The detectives say that the competition for the decathlon is very strong and that any of the students might have done something. Renard tells them to keep on it and they leave, and Hank points out that he seems off. Wu introduces them to their new intern, Ryan Smulson, who was working in records. He eagerly greets them and explains that he's been following their career since they rescued the girl. As Ryan backs away, he stumbles over wastebasket and everyone laughs.
In Vienna, Eric Renard is attending the opera and Adalind approaches him. She comments on his habits but Eric doesn't remember her, and Adalind comments that he would do anything to restore his family fortunes. The talk turns to betrayal and Adalind mentions Eric's brother Sean and hints at the Grimm. Eric offers her a shoulder to cry on and they go back into the opera together.
At the apothecary, Eddie is lecturing one of the customers about the tea that he's purchasing until the man says that it's fine as long as it's the same tea he always gets for his wife. As he leaves, Renard comes in and asks for something to stop obsessive behavior. Eddie asks him some questions to pin it down the nature of his feelings. When Renard says that it's a woman, Eddie says that understands and suggests that it could be some kind of potion. The captain admits that it's possible and Eddie says that he can have something for him the next day. Renard refuses to give his number and says that he'll come back to get it.
At the Higgins home, Pierce is studying when Jenny calls him. She's surprised to discover that he's doing homework because his mother claimed it would get his mind off of things. Jenny still blames herself and says that she's going to the bleachers to get some fresh air. She invites Pierce to join her and he says that he'll be there in a bit. As he hangs up, Pierce winces as he gets a headache.
At the school, Jenny goes to empty bleachers and someone calls to her from beneath the stands. She goes to investigate and something attacks her.
Hank and Nick get the call and Wu shows them Jenny's body. The detectives recognize her from the interview that morning and find a wristwatch in her hand. There's an engraving on it with Pierce's name on it and Nick says that if he's a Lowen then Higgins could have killed Jenny. They go to the Higgins house where Pierce is shooting hoops and push him in the hopes that he'll reveal himself. Nick asks what time it is and Pierce says that he doesn't know where his watch is. They show it to him as Dr. Higgins comes out. She confirms that she was with Pierce and they inform the mother and son that Jenny was murdered. Nick demands to know when Pierce saw Jenny last and the Grimm sees mother and son both revert into a different Wesen, a turtle-like Genio Innocuo. Dr. Higgins realizes that Nick is a Grimm and shields her son, and they explain that Jenny had Pierece's watch in her hand. Dr. Higgins insists that someone must have taken the watch and given it to Jenny. Dr. Higgins takes her son inside and Nick admits that whatever they are, they're not Lowen.
Pierce lies down in his bedroom and his mother brings him some hot chocolate. He admits that he still has a headache but claims that it's getting better, and Dr. Higgins says that she loves him and tells him to get some rest. Once she leaves, Pierce starts to drink the hot chocolate but spills it on his pillow. As he takes the pillowcase to the washer, he discovers that it's filled with bloody water. Dr. Higgins comes back and quickly closes the washer door and takes him back to his room. Anker calls Dr. Higgins from the school to inform her that he's pulling the school out of the competition. She objects but Anker insists that his decision is final and asks to speak to Pierce. Dr. Higgins hangs up and tells Pierce what Anker has decided. Pierce angrily says that the coach can't do that and stalks off.
Nick and Hank go to the trailer and find a journal entry from a Grimm who found the reclusive Genio Innocuo in the Galapagos Islands. The Grimm said that they were passive and didn't recognize a Grimm, making it easy to kill them. Nick figures that someone planted the watch and they wonder if Pierce is working with Anker. They go to see Anker and find out what his alibi is for the time of Jenny's murder. When the detectives go to the coach's home, they discover that someone has torn the place up. They follow the trail of blood to Anker... torn apart the same as Brandon and Jenny.
Eric takes Adalind to his family castle and she explains that she fell under Renard's sway and her mother did as well. The Royal explains that Renard is a half-Royal when one of his father's mistresses was a Hexenbiest. During the resulting scandal, the mistress, Renard's mother, yanked her son out of a Swiss school and took him to America. Eric assures Adalind that he has no prejudices against Hexenbiests and asks why she came. Adalind says that they have a lot in common: Renard and the Grimm. She explains that she has met Nick and Eric wonders how well she knows him.
Pierce calls Nick and says that he knows who killed the three people. Dr. Higgins barges in and Pierce runs away, dropping the phone. She catches up to him as he clutches at his head and says that she should have told him sooner. Pierce figures that his mother killed them and runs to the washer and takes out the clothing. He's surprised to discover that they belong to him, and his mother says that she didn't want anyone to hurt him. She talks about the changes and says that she was trying to give him a trait that she never had. Pierce stares at her for a second and then reverts into a Lowen form and attacks her.
Nick and Hank pull up and hear Dr. Higgins scream. They split up and go into the house and Nick finds Dr. Higgins lying on the floor. Pierce attacks him and Nick manages to knock him out without killing him as Hank arrives and pulls him off. Dr. Higgins tells them that Pierce doesn't know that he's part-Lowen. She made him that way before he was born by adding to his genetic material. Pierce never knew and never remembered how he was transforming and attacking his friends. As they talk, Pierce slips away and Hank stays with Dr. Higgins while Nick runs after Pierce.
Nick calls in for reinforcements and puts an APB out on Pierce. Meanwhile, the boy runs down the street, reverts to human form, and realizes that he's covered in blood. He heads for the water tower in the park but the cops spot him. Nick goes up to talk to him and Pierce says that he killed his friends. He transforms into his Lowen form and talks of Pierce as a separate person. The Lowen explains that he made sure that Pierce was the best by eliminating the competition. As Pierce continues transforming back and forth, he tells Nick that there is no answer and there's only one option if he doesn't want to hurt anyone. He jumps off the side of the building but Nick grabs his hand and handcuffs himself to the boy, and then pulls him up.
Later, Renard informs the detectives that the DA is going to charge Pierce with three charges of murder. Nick says that Dr. Higgins' genetic manipulations in utero are probably responsible. The captain admits that it's a tragedy and that Pierce will have a tough time in prison.
As Pierce is working in the prison kitchen, two of the prisoners start harassing him and he warns them to stay away. When they don't, he transforms and attacks them.
Renard returns to get the antidote from Eddie, who explains that he talked to Rosalee and all they can do is provide a damper on his ardor. They would need to examine the other afflicted person to administer a dual treatment, and Renard says that it's impossible. Eddie warns Renard that if untreated, the symptoms will get worse and eventually Renard will lose control and attack anything between him and the person that he has fixated on.