Tell me O'Muse, from whatsoever source you may know them.
Juliette is at home and notices cat scratches on her hand. She tries to focus on the past and remembers Nick telling her that Adalind is responsible and that she's a witch.
The next day, Nick comes down for breakfast and Monroe suggests that they have dinner that night. Nick agrees and meets Hank for coffee after his partner returns from vacation. He's surprised to learn that Hank tore his Achilles' tendon during a ziplining incident in Hawaii. Hank sheepishly admits that he was ziplining with his ex-wife, Nadine. As Nick tells him what happened, they hear nearby gunshots and Nick runs to investigate. He goes to a local bookstore and discovers that someone has shot the writer, Evan Childs. The detective spots a man, Anton Cole, dragging a woman away. Anton Woges, revealing that he's a Lusiant-Pecheur, and he jumps out the window and into the river below.
Later, the police secure the crime scene and Wu talks with the woman, Khloe Sedgwick. She says that she was Anton's ex-girlfriend and Wu passes the information on to Nick and Hank. They go to talk to Khloe.
Anton swims to shore in his otter form, unharmed.
Khloe tells the detective that she broke up with Anton six months ago and started dating Evan. However, Anton wouldn't stay away and kept visiting her at home. When Nick wonders why she didn't call the police, Khloe says that guys easily fall for her and won't stop. She kisses Nick's hand, thanking him for saving her life. Nick is momentarily dazed and then says that they'll assign an officer to watch her apartment. As Khloe leaves, the officers get Anton's address and head there. The landlady lets them in, explaining that Anton spoke about how Khloe was his inspiration. Anton's apartment is filled with portraits of Khloe in a variety of . There is also one painting showing Evan dead, shot in the head, and they figure that shows Anton's crime was premeditated. As they look around, Juliette calls and invites Nick to dinner. Distracted, he accepts, and then stares at a discarded photo of Khloe.
Back at the station, Nick makes a sketch of Anton's Wesen face and shows Hank. Hank wishes Nick well with his date with Juliette and goes to physical therapy. However, Nick goes to Khloe's apartment instead and says that he has some follow-up questions.
As she works on dinner, Juliette calls Monroe and tells him that Nick is having dinner with her. The Blutbad is surprised but figures that Nick forgot to tell him, and Juliette admits that she's nervous about getting together with Nick. Monroe assures her that Nick has been looking forward to being with her for months and tells her to take it slowly, and Juliette thanks him for his advice.
Nick tells Khloe that they didn't find Anton's body in the river and have to assume that he's still alive. He shows her a photo of the painting that Anton made of Evan's death and asks about the portraits. Khloe admits that she modeled for him along with other artists, and that she's attracted to men that see the world differently. She talks about how she inspires artists and when Nick asks how, Khloe kisses him. She then says that's how it starts but she can't control it. The woman looks at Nick and says that she can sense something powerful within him. Surprised, she Woges, revealing elf-like features, and then realizes that Nick is a Grimm. She apologizes but Nick assures her that it's okay.
Before Nick can say anything else, Monroe calls him to ask about dinner. Nick remembers that he's supposed to be at Juliette's and tells Monroe that he's in the middle of an investigation. The Grimm hangs up and tells Khloe that he has to go.
Anton breaks into a paint store.
Nick goes to Juliette's house and apologizes for being late, claiming he was working on a case. As she warms up dinner, Juliette starts to apologize only to discover that Nick is staring out the window, entranced. Nick's mind is filled with memories of Khloe and he doesn't hear Juliette apologize for how she's been treating her. He finally says that he's been feeling off because of something at work and walks out.
When Nick gets back to Monroe's, he tells the Blutbad that he didn't talk with Juliette after all. Monroe is surprised since Juliette thought it was going to be a big moment, and Nick angrily tells him to stay out of his personal life. He tells Monroe to get his own life and walks out. Juliette calls Monroe and asks if Nate hates her, and Monroe calls Hank to see if something is going on with Nick's job. Hank isn't aware of anything and tells Monroe that he'll look into it.
Nick goes to a bar to get a drink, and Hank calls and confirms where he is. When Hank joins him, he discovers that Nick is drawing a sketch of Khloe's true face. As Nick explains that it's Khloe, a guy comes up and expresses his admiration at the sketch. When he asks to show it to his girlfriend, Nick punches him in the stomach and walks out. Hank threatens to arrest the guy to keep him quiet and then picks up the discarded sketch. He takes it to show Monroe and Rosalee, telling them what Nick did. Monroe suggests that they all go to the trailer to check out the Grimm journals.
Anton takes the stolen paint cans to a city street and starts spreading it around.
At the trailer, Monroe finally locates a reference to the Musai, a Wesen that matches Nick's sketch. In 1888 a Grimm met with Gaugin, who was attacked by Vincent Van Gogh. The Grimm discovered that a prostitute, Rachel, was influencing Van Gogh and he eventually cut off his own ear. According to the Grimm, a Musai's kiss is highly addictive and inevitably ends in madness and death. The Wesen figure that Nick is safe until Hank tells them that he saw Khloe kiss Nick's hand, and they wonder where they can find the Grimm.
Nick breaks into Khloe's apartment and she comes to investigate the noise.
The next day, a bleary Nick staggers into the station and Hank points out that he's wearing the same clothing from the previous night. Nick admits that he doesn't remember what happened, and snaps at Hank when he asks about the Musai. Hank calls over Renard to look at the footage they've obtained of Anton's break-in, and informs both men that Khloe has a history of dating men who have gone insane after dating her. Wu comes in and tells them that they have a vandalism report that they have to check out personally.
At the spice shop, Rosalee and Monroe go through her books and discover that there is no known cure for the Musai's kiss. Rosalee figures that the only way they can break Nick's induced obsession is with true love. Juliette comes in and asks Monroe for the key to the trailer so that she can go back there alone to recapture her memories of the night she went into a coma. Rosalee agrees with her and convinces Monroe to give Juliette the key.
The four officers go to the street and discover that Anton has created a giant painting of Khloe. Nick leaves when the others aren't looking and Wu goes after him. Once they're alone, Hank tells Renard about the Musai and their ability to influence men.
Juliette enters the trailer and concentrates, trying to remember the night in question. She finally remembers everything Nick told her about the Grimms and the Wesen.
When Hank gets back to the station, Monroe calls to tell him what they've found out. Hank figures that Nick will go back to Khloe's apartment and leaves with Renard. Meanwhile, Juliette returns to the spice shop and tells Monroe and Rosalee that she remembers everything. She admits that she didn't believe Nick then, and realizes that he friends do believe Nick. Juliette tells them that now she believes Nick and asks where he is, and they hesitate.
Nick slips into the apartment past the officer on duty and starts to kiss Khloe. Anton is hiding there and attacks Nick, who easily knocks him down. Khloe tells Nick that she can't be with Nick as long as Anton is alive, and Nick draws his gun and prepares to shoot the Wesen. Renard and the officer on duty burst in and handcuff Anton, and Renard holds Nick back.
Monroe and Rosalee explain that a Musai is influencing Nick. Much to their surprise, Juliette accepts the story without question, figuring that it's similar to what happened to her. Rosalee agrees but warns her that she and her love for Nick are the cure.
Hank and Renard interrogate Khloe at the station and tell her that they know what she really is. Khloe insists that she has no control over her kiss' influence, and that Nick gave in more quickly because he's a Grimm.
Outside in the main room, Nick sketches on a piece of paper. An officer tells him that Anton has been booked and Nick goes to Anton's cell.
As Hank and Renard wonder what to do with Khloe, they discover that Nick is gone. They find the sketch he was working on and realize that he's drawn Anton, shot in the head in his cell. Monroe, Juliette, and Rosalee arrive.
Nick prepares to shoot Anton in his cell, but the others arrive and tell him to stop. Juliette approaches Nick and gets him to look at her, and he finally drops the gun as his mind clears. Juliette says that she's there for him, just like he was there for her. Anton reaches for the discarded gun through the cell bars, but Renard easily stops him.
Later, Renard goes back to the interrogation room and tells her that she's in luck. He's going to let her walk, but tells her to leave Portland and never come back. When Khloe wonders why she should, Renard Woges and tells her that the Hexenbiest side of him won't be so forgiving.