And they lived happily ever after.

Investor Bernard Aidikoff has confirmed that there’s a warrant out for his arrest in a Ponzi scheme. As the police try to break down his door, he kills himself.

Arthur Jarvis hears about Aidikoff’s death and calls his wife’s godfather, Spencer Harrison, to tell him that the company’s money is gone. Spencer tells Arthur to go home and they’ll talk later. When Arthur arrives at his expensive home, he discovers that his attractive wife Lucinda has just bought several new dresses for a charity ball that night. He avoids telling her about the company’s financial straits and compliments her, and then goes to see Spencer as he arrives. Arthur admits that he moved all of the company’s funds to Aidikoff and borrowed against his and Lucinda’s house. Now he has three days until margin call and doesn’t know what to do. Spencer tells him that he’ll have to ask for money from his wife’s stepmother, Mavis Curfield. Arthur is understandably reluctant to do so, and is interrupted when Lucinda comes in to show off her new dress and greet Spencer, an old friend of her deceased father Henry.

Spencer and Arthur meet with Mavis, who flat-out refuses to give them the money. She points out that Arthur has all but ignored her since he married Lucinda and orders them out. As Arthur leaves, Spencer reminds Mavis that it was thanks to his friend Henry, who Mavis married, that she has any money at all. She tells him that she’s earned everything since Henry’s death and tells him to face reality. When Spencer says that Lucinda is only asking for what she deserves from Henry’s estate, Mavis tells him that Lucinda will have to deal with her own financial losses and says he should get a life of his own.

That night, Mavis is trying to sleep when she hears something moving beneath the bed. She looks and sees a man- batlike creature that lashes out at her. Mavis runs out into the hallway but the creature cuts her off. It gives off an unearthly ultrasonic screech that shatters every piece of glass in the house. Mavis’ eyes rupture and her eardrums shatter from the sound and she falls over the banister to the floor below.

Nick is in bed dreaming about his recent encounter with the wesen thieves who were seeking the coins, mixed with nightmares about his parents’ fatal car accident. Juliette wakes him up and he tells her what he was dreaming about. He explains that for a long time after his parents’ death, he wished that he had died with them. It was only with his Aunt Marie’s help that he eventually came out of his depression. Juliette points out that the fourth man, Farley Colt, knew about Nick’s parents and says that she’ll call the town of Rhinebeck where they died and see if the police know anything.

Lucinda comes down to get Arthur and finds him drinking. He says that he was worried and admits that he doesn’t want to lose her beautiful smile because it would kill him.

The next morning, Mavis’ daughter Tiffany arrives at the house while talking to her younger sister, Taylor. Tiffany finds Mavis dead in the foyer and calls in the police. Nick and Hank arrive and Wu briefs them on the bizarre murder, the shattered glass, and the lack of evidence pointing to a break-in. The detectives check the upstairs hallway where Mavis died and confirm that the glass shattered as she died, not before. When they talk to the sisters, Tiffany insists that Arthur killed Mavis. They explain about how Arthur is married to their stepsister and lives within a mile of the Curfield home, and that he was there the day before asking for money without success. They also tell Nick and Hank about Spencer, who always considered Mavis beneath him because he believed she married his friend Henry for the money.

Juliette calls the Rhinebeck Police Department and talks to the investigating officer, Detective Arnold Gubser. He admits that he doesn’t have anything new on the case. When Juliette tells him that she’s calling on behalf of a police officer, Gubser says that he’ll call Nick with anything he can find.

Nick and Hank go to talk to Arthur, and Juliette call to let Nick know that Gubser will call him. Lucinda invites them in and takes them to the library where Arthur and Spencer are trying to save their company. Nick tells them about Mavis’ death and all three of them seem surprised. Arthur refuses to discuss his financial situation, insisting that it’s confidential, and Spencer becomes upset. When he grows angry, Nick sees him as a batlike creature. Spencer asks for a few minutes with Arthur and the detectives wait outside. While they wait, Gubser calls to tell Nick that the accident was refied as a homicide a year later. There were four possible suspects, and Nick recognizes three of them as the wesen who were after the coins. The name of the fourth man, Akira Kimura, doesn’t ring a bell.

Spencer and the Jarvises go to the station house to give statements. Arthur tells them about his request for money from Mavis, and that he kept the company finances a secret from Lucinda because he didn’t want to upset her. He had originally been set up to date either Tiffany or Taylor, but fell in love with Lucinda instead and the sisters resented Lucinda ever since. He insists that he didn’t have a sexual relationship with either sister and that they resented Lucinda’s beauty. Lucinda’s mother died when she was young and her father died two years later, shortly after marrying Mavis.

Next the partners talk to Lucinda, who appears concerned about her sisters. She admits that she had difficulty with them because she shut herself off after her father’s death. When Hank tells her that Mavis’ money all went to the two sisters, Lucinda isn’t surprised. However, she insists that she loves Arthur and wouldn’t do anything to put their life together at risk. When they ask about Spencer, Lucinda explains that he was Henry’s friend and her godfather, and has stood by her ever since her father’s death.

Spencer tells the detectives that he made and lost several fortunes. Henry brought him onboard his company the last time and in return, Spencer promises the man on his deathbed that he’d take care of Lucinda. He tells the detectives that he stayed overnight at the Jarvis home to work with Arthur on the finances

Once they’re done with all three suspects, Nick and Hank report to Renard, who is intrigued by the method of death. The detectives admit that they don’t have any leads, and Renard warns them that thanks to the Jarvis connections, they’ll need solid evidence of the murder method to make a case. Back at his desk, Nick receives an email from Gubser with the photos of the four suspects, including Kimura. Hank comes over and recognizes the three thieves, and finds it odd that they were in Rhinebeck and then happened to turn up in Portland and meet Nick. Neither he nor Nick recognize Kimura.

That night, Arthur tells Lucinda about the company finances and suggests that they move and start over. Lucinda is unhappy because he doesn’t want her to try and make amends with her sisters. As she storms out of the room, Arthur warns her that if either Taylor or Tiffany killed their own mother then they won’t hesitate to kill Lucinda as well.

Tiffany is at the manor going over the papers and talking to Taylor, who has been drinking. When a guilty Taylor suggests they give some of the family money to Lucinda, Tiffany refuses, saying that they’d never stop asking. She figures that they somehow murdered their mother and refuses to give in.

The next morning, Arthur calls Spencer over and tells him that Lucinda slipped out in the early morning. Angry, Spencer reminds him that since he married Lucinda, she’s now his responsibility and that Arthur has to protect her.

Tiffany is leaving for the morning and finds Lucinda on her doorstep. Lucinda tries to get through their differences, but points out that Mavis and Tiffany didn’t want her as part of the family. Tiffany blames everything on Lucinda, accusing her of being the spoiled princess that always got what she want. She figures that Spencer and Arthur somehow killed Mavis and gets into her car. Lucinda says that she wants Tiffany to hear one more thing from her… and then turns into a bat creature and unleashes an ultrasonic scream at her stepsister.

Nick and Monroe go to the trailer to check the journals and find an entry matching the description. The wesen is a murciélago, The bat creatures can generate an ultrasonic screech capable of fatally rupturing the human body. The only defense against them is a murciélago matraca, a sirenlike device that generates a counter frequency sound wave. They two men find it and try it out, and end up shattering a nearby bottle.

Nick goes back to the Jarvis manor to confront Spencer alone. He finds Arthur and Lucinda there, but Arthur has no idea where Spencer has gone. Lucinda insists that Spencer had nothing to do with Mavis’ death, but Arthur admits that Spencer was angry at Tiffany and went back to the Curfield house to ask her for the money. Nick calls Hank and tells him to bring a squad of men and meet him at the house.

When Spencer gets to the Curfield house, he finds Tiffany’s ruptured body outside in her car. He realizes that Lucinda killed her stepsister and will be going after Taylor next. Before he can leave, Nick arrives and arrests him. The detective doesn’t believe the murciélago’s claims of innocence and turns him over to Hank and the cops when they arrive. When Hank wonders how Spencer killed Tiffany and Mavis, Nick covers it up and claims he has no idea.

Back at the station, Renard warns the detectives that without a weapon or deny, they can’t connect Spencer to the murders. Wu tells them that Spencer has announced his intention to confess. Nick and Hank go in and he says that he doesn’t see any reason to lie since he and Nick know what each other are. Hank doesn’t know what he means and Spencer realizes that he doesn’t know about Grimms and wesen. He then announces that he killed Mavis and Tiffany because they refused to loan money to the company. When Hank asks how he did it, Spencer tells him the truth, explaining that he used an ultrasonic beam. Hank figures that he plans to plead insanity and leaves, and Spencer says that he told the truth so that they could speak alone to Nick. He tells Nick that Lucinda is a sociopath and that he’s indirectly responsible because he didn’t stop her like he promised her father. Spencer has spent years making sure Lucinda has everything she ever wanted so that she wouldn’t get upset and lash out. Nick is skeptical of the claim and Spencer warns him that Lucinda will kill Taylor next so that she can inherit the family fortune.

As Nick goes to call Monroe and have him bring the matraca, Hank comes over. Nick suggests that Spencer isn’t the murderer and Hank agrees, figuring Lucinda as the killer. Meanwhile, Spencer uses his ability to blast open a window and escape the interrogation room. He goes to the Jarvis home and finds an injured Arthur, drinking heavily. Arthur says that he finally tried to stand up to his wife and she told him that she never loved him.

Nick calls Taylor at home and tells her to lock herself in. However, Lucinda is already in the house and advances on her stepsister. Nick and Hank break in just in time to drive Lucinda away. Hank tends to Taylor while Nick goes after Lucinda. As she runs into the garage, Monroe arrives with the matraca. He warns Nick that they’ll have to drive her out of the garage and they crank up the matraca. It shatters everything breakable in the garage and the ultra-high frequency pitch forces Lucinda to leap out the back window. As Nick and Monroe run around, Spencer finds Lucinda first. She begs him for help and Spencer says that he should have helped her a long time ago.

Nick and Monroe hear another screech and get to the back of the garage to find Spencer standing over Lucinda’s ruptured body. He learns over her, regretful that he had to kill his goddaughter. However, Lucinda manages to rip out his throat with her dying breath.

Later, Nick shows Hank and Renard the matraca and claims that Lucinda and Spencer used it to murder Mavis and Tiffany. The two cops accept his story. When Nick returns home, Juliette apologizes for digging up the past, but he tells her that it’s okay. He looks at the photo of the fourth unknown man, Kimura, and tells his fiancée that he’s going to have to deal with him.