By Jay Conaty

Last night’s CSI: Vegas made for quite an eventful hour of TV.

Not only did the CSI lab become a crime scene, forcing Max to put the entire lab on lockdown, but for a hot minute Agent Park became suspect number one in the Hodges case. Meanwhile, Sara and Gil finally found their man. That’s right. We finally know who set Hodges up. And yes, it’s the last person we expected.

Meanwhile, Josh and Allie (in what would have made a perfect Halloween-themed episode) investigated a ritualistic double killing in a spooky clown-themed motel that appeared to be the work of a serial killer already behind bars. They also got mistaken for a couple. Again. This is going to be a thing every week, isn’t it?

The episode kicked off with Gil bringing Park up to speed on all things Hodges, as the pair examine the peculiar smudges on the wall of Martin Kline’s house. It’s Luminol, a standard chemical the techs use to determine the presence of blood. (So that’s what the guys have been squirting on q-tips all these years!)

Whoever used Luminol on Kline’s wall was double checking their own clean up job. Were they accidentally injured when the grenade that killed Kline went off? Probably. If they can test the chemical, maybe they can at least match it to a commercial brand. It’s not a blood sample, but at least it’s a clue.

Pictured L-R: Matt Lauria as Josh Folsom and Mandeep Dhillon as Allie Rajan Photo: Sonja Flemming/CBS

The Luminol reveals something more. It’s been tainted with another chemical reagent. Both are from the lab. Whoever covered their dirty tracks had access to the lab’s chemicals. It looks like they accidentally swapped out bottle nozzles. If the CSI’s can test every tech’s testing kit and find the person with the mismatched reagent bottle with the Luminol nozzle, they will know who cleaned the scene of Kline’s murder.

Meanwhile, Detective Nora Cross is back, and urging Maxine to have trusted her earlier. Hmm… Ok. However when she is brought up to speed by Maxine, and subsequently learns there might be a killer in the lab right at that very moment, Cross’ attitude becomes decidedly less friendly.

“Find them,” she tells the gang. “Then maybe I won’t recommend the D.A. throw the book at all the rogue CSI’s I’ve met.”

As the lab search begins, Maxine is alerted of a new, potentially far more serious situation. A collection of 7 grenades have gone missing from the seized weapons store. Grainy video footage of the area shows a man (from the waist down) returning an empty weapons box — minus the grenades — five minutes before lockdown. Whomever took those grenades is still in the building. And armed. Also, that person is not wearing shoes.

Things get weird fast when we discover Agent Chris Park is the culprit. Additionally, the mismatched bottle is his. Is cuddly Park really the mastermind behind the Hodges case? No, he isn’t. Park took the grenades as part of an investigation, and he lost his Luminol bottle a couple of weeks ago on a different case entirely. (The shoe thing is just a red herring as it turns out.)

After some hard scrutiny, Maxine realizes Park is sloppy, but not guilty.

Pictured: Jay Lee as Chris Park Photo: Sonja Flemming/CBS

Sara and Gil look into Park’s previous investigation involving a murder in a car. They check out the blood-spattered car in an impound lot themselves and discover what looks like a large quantity of spilled Luminol on the carpeting on the floor inside the vehicle. It looks like Park’s bottle may have fallen, rolled, and come to rest for some time (spilling some of its contents) before bing picked up by an opportunistic individual.

Sara finds dandruff flakes on the floor belonging to said opportunistic individual, and DNA-tests them against a list of people who had access to the car investigation. Bingo! The overwhelming evidence points to Anson Wix the attorney for the class action lawsuit of wrongful imprisonment against the state.

Wix is the man who is working diligently to free thousands of of incarcerated villains the CSI’s have worked hard to put away over the years, and he stands to make millions representing them all.

A few flakes of dandruff and a missing bottle of chemicals won’t be enough to collar Wix. Sara and Grissom will have to consider their next move carefully.

Pictured L-R: Rebecca Metz as State Trooper Stubb, Mandeep Dhillon as Allie Rajan, and Matt Lauria as Josh Folsom Photo: Sonja Flemming/CBS

With the lab locked down, Allie and Josh are forced to work their case in the field this week. The pair are called out to investigate the creepy death of a young woman whose throat has been cut. Her body is later posed in a clown’s costume, with a paper flower in her coat’s buttonhole. While suspicion immediately falls on her boyfriend, who has gone missing from the run-down clown-themed hotel they were staying at, there are a collection of other worthy suspects lurking about too, from the hotel’s dispirited owner to the surly housekeeper with a violent past, to a pair of meth addicts sharing a room nearby.

However, the murders (the boyfriend shows up dead at a later point too, his body also carefully arranged in the same manner) both seem to point to the handiwork of Jeremiah Dalt, aka The Gemini Killer, a notorious serial killer famed for murdering young couples. However, with Dalt currently behind bars, Josh and Allie struggle to put the pieces together, even after Dalt’s fingerprints are found on the paper flowers pinned to each victim.

Eventually, the tears of a clown give our duo the break they need. Both victims display tear tracks on their cheeks. It’s Josh who realises the tears aren’t those of the victims but their reluctant killer.

Pictured: Matt Lauria as Josh Folsom Photo: Sonja Flemming/CBS

DNA evidence leads us to the beleaguered motel owner who, we learn, was forced to commit the murders by Dalt. The Gemini Killer was famous for recreating a map of the Gemini star constellation on his former murder spree, with each killing marking another point in the constellation. The clown motel was set to be the final point on his murder map.

Now behind bars, Dalt befriended and then threatened a prison guard into contacting the hotel owner on his behalf. Dalt, feeling pretty confident Wix would get him out of prison in the very near future, threatened the lives of both mens’ families. Both men, fearing Galt would be free to kill again soon, carried out his wishes to the letter to save their loved ones.

Allie and Josh bring in their guilty men, having learned a little something more about each other along the way. Allie used to be in a punk band in college. Josh is deathly afraid of clowns.

CSI: Vegas continues Wednesdays on CBS.

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