Booth (David Boreanaz
) and Brennan (Emily Deschanel
) eat lunch at the diner while the latter pages through applications. She has decided to include Booth in the assistant-picking process. "I'm making an effort," she says. Booth gets a call from Ken Nakamura (Brian Tee
), whose sister has not called in five days. Sachi, a 21-year-old girl, has been staying in Washington D.C. for two months. Booth does some checking and gets disturbing news. The woman's car has been discovered abandoned in a bad part of town. B&B head the spot. An officer (Katherine Kamhi
) informs the pair Nozomi Sato (Jane Park Smith
), Sachi's roommate, is also missing. Brennan spots something in nearby marsh: a Japanese mask. Underneath that mask is a human head. Yikes.
Back at the Jeffersonian, the team examines the head. Cam (Tamara Taylor
) estimates the head was in the water for four days or so. Meanwhile, Ken has arrived from Japan along with the androgynous Dr. Tanaka (Ally Maki
). Booth announces the two visitors will be assisting in the investigation, despite such practices going against protocol. Moments later, Brennan and Tanaka make a positive ID: Sachi Nakamura. "I'm very sorry," Brennan tells Ken.
Ken is stoic, but clearly upset. He blames himself for his sister's death. Ken also shows Booth a flier for modeling services. "The man who took these pictures said he could make her a model," Ken explains. It's not much, but it's something.
Moments later, Booth and Ken visit the photographer, Mr. Strutt (Bumper Robinson
), who explains Sachi and Nozomi worked at a local Japanese tea hangout called Pappa Puffs. Booth and Ken arrive at Pappa Puffs to find women wandering around wearing anime masks. Booth shows a picture of the victim's mask to the owner, Bruce Takedo (Yuji Okumoto
), who says it belonged to Nozomi. He then explains the girls started working for an Elegant Escorts. "I don't believe you!" Ken says. "That's my sister!"
Cut to the diner, where Angela (Michaela Conlin
) remains fascinated by the unanswered question of Tanaka's gender. Man or woman? No one seems to know. B&B, meanwhile, confront Elegant Escorts Jimmy (Robert Wu
). The little punk doesn't want to cooperate at first. "Just know, as of right now, your business is done or, you give me something shiny to distract me," Booth says. That something shiny turns out to be the name of a Nozomi's recent client. Apparently, this client liked the "rough stuff."
Back at the lab, Hodgins (T.J. Thyne
) has discovered bird vomit on the victim's head. More interesting is that the vomit comes from a bird indigenous to an area miles from where the body was found. He, Cam and Tanaka examine a map. "Why would someone cut the head off a body here and drive miles away to dispose of it here?" Cam asks. Excellent question. Either way, the search team needs to head to a different spot further north. Sure enough, searching the new area yields almost immediate results: the remainder of Sachi's body. Back at the lab, Brennan examines the decomposing body. Ken turns his head away in disgust. Cam, in the meantime, liquefies the brain to reveal a small splinter. Hmm.
B&B head to a massage parlor to discover "rough stuff" client Paul Vogler (Larry Clarke
) in the middle of a rubdown. He claims never to have met Sachi, saying Nozomi was the only escort he was seeing. "I'm not saying another word to you people without my lawyer," Vogler says. Back at the lab, Angela has hacked into the Strutt Photography Web site and discovered voyeuristic photos of Sachi taken with a long lens. "Classic stalker photos," Camille says. Quips Angela: "Maybe it wasn't just pictures he wanted to shoot." Tanaka, in the meantime, has examined the skull and determined the cause of death was drowning.
But where was she drowned? Hodgins has a few possible leads. First, the splinter found in the victim's brain came from an ornamental bamboo display. Cam theorizes the woman was decapitated and her head placed on a bamboo spike. Second, she was drowned in fresh water -- not the salt water marsh where the head was discovered. Booth points out the photographer has a decorative pool in his office. Hmm.
Cut to Strutt's office, where Brennan collects samples from said pool. Strutt admits to sending especially cute and adventurous girls to Jimmy for a "finder's fee." Beyond that, the photographer claims he is clean. Back at the lab, Hodgins discovers Sachi was NOT drowned in the Strutt pool, as the water contains chlorine. Ken, in the meantime, theorizes on why his dead sister's head ended up impaled on bamboo. In feudal Japan, a head was placed on a spike as a warning. But why Nozomi's mask? "Because the warning was meant for Nozomi?" Angela asks. Exactly. "But what did my sister do to get killed?" Ken asks. Another excellent question.
And one that might be answered sooner rather than later. Why? Because Nozomi has been caught trying to leave the country. Sweets (John Francis Daley
) interrogates the woman, who is clearly shaken up. Nozomi only blinks away tears and remains silent, though. Brennan, meanwhile, has made a breakthrough. The head was not decapitated with a katana sword -- the cut is simply not clean enough. Instead, she describes the specifics of the cuts to Angela, who enters the date into her computer. Seconds later, a crude representation of a blade appears on the screen. "I've seen this knife before," Brennan says. "It's a Marine knife. The hook is used for cutting line and cord." Doesn't Jimmy, the escort-service owner, live on a boat?
Booth and Brennan bring Jimmy in for questioning. Brennan reveals a familiar-looking knife was found in the man's boat. "The serrations are consistent with the tool markings on the bone," she explains. Sure enough, blood is found in the sheath. But the case isn't closed just yet. "It proves he cut off her head," Brennan notes. "She died by drowning." Jimmy, who admits to putting Sachi's head on the spike, demands a deal before he reveals the true killer. Booth has another idea. He throws the snot-nosed punk up against the interrogation-room wall -- but Jimmy remains defiant. Should they make the deal? "Cut the deal," Ken tells Booth.
So Jimmy talks. As his story goes, Paul Vogler got a little too rough with Nozomi one night, which made roommate Sachi very, very angry. Sachi threatened Vogler, telling the man she would call her "cop brother" if he ever touched Nozomi again. In a panic, Vogler pushed Sachi into his decorative pond, accidentally killing the girl. Jimmy was then paid to clean up the mess and warn Nozomi. Case closed.
But not the episode. Angela still wants to know if Tanaka is a man or a woman. So, she hugs the good doctor tightly. "It moved," she tells the team. "It's a guy."