A dead man, somewhere in New York City, is holding a burning candle. He's surrounded by a red cloth and a glass bowl filled with blood.
Meanwhile, in the loft, Castle is rolling around in bed with his ex-wife Meredith. As they reminisce about the good times -- and the good sex -- they've had, Meredith blurts out that she's moving back to the city. Castle tenses... not too pleased about this.
Esposito runs down the crime to Castle and Beckett -- the victim is an unidentified African-American male in early-20s who suffered multiple stab wounds. Castle recognizes the red flannel, the candle and the bowl of blood as part of a Vodun ritual. He tells them to check the victim's mouth, where they find a white fabric bundle containing an odd-looking silver charm, along with a mysterious symbol drawn in red ink on the fabric. Despite his knowledge, Castle doesn't recognize the symbol.
Beckett accompanies Castle to his loft to go over the Vodun research he did for his sixth Derek Storm novel. Annoyed that Castle's only research source seems to be his own book, Beckett makes for the door, only to run into Michelle, an attractive African-American woman -- Castle's other source.
Michelle explains that the symbol is a vever, a representation of the one who can open the crossroads to the spirit world. The charm is an offering to a Vodun saint, in this case Ogun -- who is usually called upon to help find something that's been lost. Apparently the man was murdered because he had something the killer desperately wants. And he's not going to stop until he finds it.
Just then, Beckett gets a call from Ryan. They found a female murdered in the same ritualistic fashion. At an Upper Westside apartment, Castle and Beckett discover Darcy Cho, a young lawyer, lying on flannel cloth and dead from multiple stab wounds. Same paraphernalia as the first murder and a charm in her mouth, as well. Beckett also finds a shredded purse lying on the floor next to the body. Studying Darcy's pose, Castle is sure the murderer is still asking the spirits to guide him. In other words, he didn't find what he was looking for.
At Marlowe Prep, Alexis gets called into the principal's office and finds her mother there. Meredith has bad news for Alexis -- her grandfather has passed away. Before Alexis can protest, Meredith whisks her away. Outside, Meredith explains that she had lied simply because she needed some Alexis time -- they're going shopping.
A match on the man's fingerprints comes in from the INS database -- the victim has been identified as Jamal Buonsi, a Nigerian national enrolled as an exchange student at NYU. His student visa had expired a year ago, but he'd secretly decided to stay. Esposito checks with the family Jamal lived with when he was in school and discovers that their 13-year-old son had been keeping in touch with Jamal. Esposito hands over Jamal's cell phone number, noting it's billed to an address on East 3rd street -- right near Darcy Cho's law firm.
At a rooftop courtyard, Beckett and Castle reach an apartment. They hear music and muffled voices speaking in a foreign tongue coming from inside. An African man in his 20's answers Beckett's knock, but tries to slam the door shut after she identifies herself as NYPD. Beckett bursts in with her gun drawn. No one in the small apartment admits to knowing Jamal Buonsi, even though his cell phone was billed to their address. Castle then notices a piece of red flannel peeking out from under one of the beds. He also notices paraffin candles and a glass bowl.
Castle and Beckett interrogate Azi, the man under whose bed they found the paraphernalia. But Azi claims the items are not his. Beckett gets Azi to tell her who does own the items -- Charles Oni. Apparently, Oni also owns the apartments and the businesses where the Nigerian immigrants work. Furthermore, Oni made Azi show him how to invoke the spirits using the Vodun objects.
At the precinct, Beckett discovers that the apartment is registered to a "Robert Burnett" with a P.O. box in Jersey. Also, according to Esposito, no one at the law firm ever heard of Jamal Buonsi, nor was there anything suspicious in Darcy's client list.
Just then, Meredith barrels into the precinct. She's allegedly there to drop off Alexis, but she's really there to get a look at Castle's latest inspiration -- Beckett. Meredith sees the photo of the purse on the murder board and notes that the bag is a knock-off. This helps Beckett put it all together: Cho most likely bought her knock-off purse in a stall owned by Charles Oni on Canal Street, the same stall where Jamal worked.
At the loft, Martha complains to Castle about Meredith. Has he considered how disruptive it's going to be having Meredith back in New York? What's more, Martha made a few calls and found out the reason Meredith wants to relocate to New York is because she can't get any work in Los Angeles. Martha thinks it's insulting that Meredith thinks she can waltz into New York and start taking Broadway roles away from "real" theatre actors.
The team descends upon Canal Street with a search warrant for Charles Oni's stall. They break into the shuttered stall to find it ransacked. Esposito notices a large Vodun sign in red chalk on the floor. It's different from the one found in the victims' mouths. Castle recognizes it as the symbol for death. In other words, Charles Oni has been marked for death.
Amongst the wreckage, they find a bunch of shredded purses, their linings cut out. Looks like somebody was trying to smuggle something in the bags, but what? The only person who could say for sure is Charles Oni. Becket has Esposito and Ryan call and put Oni's name on the No Fly List.
Suddenly Beckett notices Castle crossing the street and waving his hands, like he's lost his mind. It turns out he's waving at the display window of an electronics store, where a large flat-screen TV is broadcasting the view from across the street, including Oni's stall.
Thinking the trashing of Oni's store may have been captured on tape, the group approaches the electronics store's manager. However, he can't show them the video from the previous day because someone came in and bought the camera in the display window. The manager describes him as a tall black man with an accent. Not Charles Oni, but someone else. Luckily, the manager has a surveillance photo of the guy.
Across the street, Esposito gets a call -- the TSA just pulled Charles Oni from a security line at JFK, where he was trying to flee to Nigeria.
At the precinct, Beckett and Castle interrogate Oni. He initially refuses to talk, until Beckett shows him the surveillance photo. Oni's fear is palpable. Demanding protection, Oni finally reveals the man in the photo's name: Mukhtar Baylor. Baylor is a former Nigerian secret police officer known as the Butcher of Benin. He traffics in drugs, women, and whatever makes him money. Oni reveals that Baylor is looking for counterfeit passports and visas hidden inside the linings of the fake purses. He needs the documents to get his brother out of Africa before he's arrested by Nigerian officials for drug trafficking.
They head to a downtown warehouse where Baylor runs his operation. Beckett leads a TAC team inside, with Ryan and Esposito trailing. A moment later, Castle follows, sporting a custom bulletproof vest. The Tac-team moves silently through the warehouse. But... in the middle of this, Castle gets a loud ring. He's got a text from his daughter.
Sheepishly, Castle heads outside and dials his cell. But instead of Alexis, Meredith answers. She's found an ideal condo and might need Castle to co-sign the mortgage. While Castle is trying to get off the phone, he spots an SUV approaching -- and Mukhta Baylor is driving! Castle chases after the car as Baylor peels out.
Much to Beckett's chagrin, Castle fails to get the SUV's license plate number and can't even recall the exact color. Inside the warehouse, they find bolts of red flannel, glass bowls, knives and weapons, jars filled with liquid and, more curiously, yoga brochures and schedules. And, intriguingly, Castle finds the video camera from the electronics store.
At the precinct, they sit in front of a TV monitor, scrolling through the videotape. In the image's background, they can see Jamal working at Oni's stall across the street. Beckett notices Darcy Cho stopping by, after which Jamal disappears into the back of the stall and re-emerges with the purse.
As Beckett starts to fast-forward through the tape, Castle spots another woman stopping to buy a similar purse. She has a yoga mat and a cup of take-out coffee. Beckett regards the stack of yoga brochures they found at the warehouse and realizes that Baylor must be looking for this woman too. They rush out to track her down before Baylor gets to her.
At the Blissful Buddha Yoga Studio, the manager identifies the woman as Diana Edwards and tells them another cop had come looking for her just a few minutes before. Beckett realizes it must be Baylor.
They race to Diana's apartment to find her safe but wary. Beckett empties Diana's purse and rips out the lining to discover a passport inside. As Beckett is calling it in, Castle spies Baylor coming through the front door, armed with a handgun. Baylor opens fire just as Castle leaps to push Beckett out of the way. Diana runs into her bedroom as Beckett and Baylor exchange gunfire. With Beckett and Castle huddling behind the kitchen island, Baylor offers an ultimatum -- give up the passport or die.
Trapped without a clear view of Baylor, Beckett realizes she only has two bullets left in her gun. Castle pulls out a champagne bottle and shakes it vigorously to uncork it. Baylor hears a loud pop and, mistaking it for a gunshot, he leans out to return fire. But Beckett is ready for him and takes him down with one shot to the shoulder and one to the leg. Later, as the paramedics wheel Baylor out and the police take Diana Edward's statement, Beckett begrudgingly admits to Castle that he saved her life.
At home, Alexis confides to Castle that Meredith is driving her crazy. Just then, Meredith enters with exciting news -- she's been offered a role in a new indie film! Unfortunately, she now has to postpone her move to New York. She's saddened that she won't be moving back, but it was an opportunity she couldn't turn down. After Meredith sweeps out, Alexis gives her dad a look and Castle admits that his business manager offered him a great investment opportunity in a small, artsy independent film. Plus, Meredith was perfect for the part. It was an offer he couldn't refuse. Alexis nods, noting that raising one parent is hard enough -- She doesn't know what she'd do if she had to raise two. As they share a smile about it, Castle pulls her into a hug.