A girl scout leaders guide

Murder –what else? — leads to the usual team meeting at BAU headquarters, where pregnant J.J. briefs her colleagues on the latest case. Or series of cases. “Six victims have been killed in a series of burglar homicides all over central California,” she explains.

The latest pair of victims: a couple who resided in Sacramento. J.J. assures the team that each death comes courtesy of the same unsub as the DNA is a match. Also: local cops and press have already come up with a not-so-clever name: the “Highway 99 Killer.”

“What’s unique about this unsub is that after he kills them, he apparently sits down for dinner in their homes,” Hotch points out. Worse, he showers and sleeps in the victims beds. Ew. Creepy.

The team arrives at the Sacramento crime scene. Local law enforcement tells Derek that the male victim had his shirt placed over his head and his pants placed over his legs. “This may be some form of transference,” Rossi theorizes. “He pretends this is all his. He’s playing out his fantasy.” Meanwhile, a neighbor says she spotted a mysterious man on the victims porch around 5:30 a.m. The couple was killed at 1 a.m.

Rossi has an idea. He calls Reid, asking the boy wonder whether train tracks connect the last two murder scenes. They do.

Derek and Rossi walk the tracks with a train-yard operator, who explains that he occasionally sees “hobos” jumping trains. Reid, meanwhile, calls Garcia and asks her to find homes within one mile of train tracks in the area. He suspects there might be more murders than originally reported.

The team returns to Sacramento police headquarters to brief the local investigators. Hotch explains that the killer does NOT travel on Highway 99 — sorry, folks — but makes his way from crime scene to crime scene by train. Reid says that the unsub will have a rash around his mouth. Why? Because along with making his victims’ homes his own, he huffs their household cleaning products.

“If you get close to him you wont miss him,” Emily says. “He will smell like a combination of human filth and paint thinner.”

Cut to the yet unrevealed killer, huffing cleaning product from a bag while riding the rails through farm country. Will our beloved BAU team be able to catch up?

Derek and Rossi will certainly try. They come across a hobo camp, offering food in exchange for information. The hobos are of little help, although Derek notices the complex series of symbols carved and drawn onto nearby rocks and trees. One hobo draws a symbol warning the next group that the cops are looking for someone.

Back at the station, Garcia calls with disturbing news. “I found his DNA in three more cities,” she says. In other words, the killers reach stretches farther than anyone suspected. “It can happen when unsubs cross jurisdictional lines,” Hotch explains.

Garcia has even more news: the killer arrives into towns when the sales of certain crops squash, apples, etc. spike. “So he’s in town for a big harvest,” Emily says. A migrant farm worker, perhaps? Bingo!

Another dead couple has been found — and the team is on the scene. “The first few murders were five to eight days apart,” Reid points out. “This one was just one day from Modesto. If we don’t find him soon …” Yeah, we get it, Reid. The team must hurry — as usual.

And they do. Derek and Rossi, investigating the scene of a previous crime, find a symbol carved in a tree outside. J.J., meanwhile, calls Hotch and the gang. Jewelry taken from the Sacramento crime scene has shown up at the pawn shop in Modesto. Better yet, security cameras have captured a blurry photo of the seller. Dark skin, about 5-foot-8, red rash around his mouth. Hotch tells J.J. to circulate the photo.

Hotch, Emily and Reid are snooping around a local apple-picking operation when Garcia calls with what she refers to as a “triple whammy.” The movement of a group of migrant workers matches that of the killings — up until a certain point. One of its members has a long criminal record. That same workers fingerprints show up in the home of one of the victims. Ladies and gentlemen, we have a suspect.

Hotch, Emily and Reid visit the group with wich the the suspect once worked. They pass out photos of the suspect. One man recognizes the killer. He speaks softly to Emily in Spanish. “It’s his brother,” Emily announces.

She questions the man, who says his brother got the group fired from a big job and has been following them ever since. The suspect has also been giving his brother money — probably from the robberies. “He has been trouble all his life,” the man says of his hermano.

Speaking of, the killer scouts another home. A woman sleeps on the couch inside. She awakens to see a news broadcast warning viewers to “lock their doors” and “keep the lights on.” She, of course, has done neither. Just then, she looks outside and sees the killer! She SCREAMS and the killer flees.

The team gets a call: the suspect has been spotted. And wouldn’t you know it? Eye witness accounts put the fleeing suspect in Derek’s search area. Bad luck for the killer, as dedicated BAU watchers well know. Gun drawn, Derek creeps around the train tracks, exploring open box cars. He spots the killer knifing a local cop and gives chase.

Before you can say “inevitable,” the chase moves to the top of a moving train. While Derek fights with the killer, Hotch pulls up alongside the tracks in an SUV. He takes aim and shoots. The killer falls from the top of the train to the tracks below … DEAD.

Back at the station, the team discusses dinner when J.J. enters with a gorgeous young woman. Agent Jordan will be filling for J.J. while she is on maternity leave. Derek has met the woman before. “Briefly,” he says. The two smile knowingly at each other.

Uh oh. Garcia ain’t gonna like this.