Catherine heads back into Liam's lair, where he's still counting out maggots. She asks if there's a reason he's got them all clinging to duct tape, and he quips, "The evidence wasn't cooperating, so I stuck it to them." "Cute," Catherine says, and Liam grins. Then he tells her he's found black plastic shreds, as if from a garbage bag, plus this handy fake fingernail covered in tacky blue paint.
Cue Catherine kicking Sara off the microscope. Sara's all, "I have three more samples to run. When I finish it will be your turn." Catherine doesn't go for the doctrine of prior ownership. She's all, "This can't wait!" Without looking up from the screen, Sara asks, "It can't or you can't?" "Both," Catherine shoots back. She invites Sara to have a cup of coffee on her, and Sara takes off with, "The coffee's free." Wow, the PEAP counseling has really worked wonders for Sara. Either that, or she headed off to tell Gil that he's nuts to consider Catherine supervisor material. Anyway, Catherine discovers blue paint mixed with motor oil. The soundtrack gets alarmed in response.
Catherine then sashays in to drop her lab results in Gil's lap: "Oil-based blue paint mixed with motor oil." The music gets all ominous as Gil decrees, "He's back."
"He" would be the Blue Paint Killer. Let's re-acquaint ourselves with the said killer, as per Season 3's "The Execution of Catherine Willows." I've excerpted all the relevant stuff from the recap for you, thus recapping a recap and plunging us all into a post-modern abyss of self-referentiality. Do you feel like a French deconstructionist yet? Here's what you need to know:
Catherine exposits for all of us: "People v. John Mathers. Serial. Western LVU. I was a rookie." Western LVU is turning into UC Sunnydale with the mortality rate. I wonder if they're in the same athletic conference -- the DEAD 10? Gil recognizes the case -- three dead coeds, all sexually assaulted with no semen found. The women were found dead and bound in garbage bags. Catherine explains, "The strongest evidence was victim #3, Charlene Roth. Mathers, a campus security guard, got murder one for that."
But just before he's executed...
Cut to Catherine catching Gil in the Labitrail and telling him, "A stay. New evidence -- hair analysis. I've already overnighted the six pubic hairs found on the victim to Norfolk Department of Criminal Justice for mitochondrial DNA analysis."