Cut to Gil wandering around the art therapy room. He happens to notice an amphora missing what looks a lot like the pottery handle used as a shiv a few moments ago. We find out that Adam was making the piece on Monday, but he never had a chance to fire it because Creepy Nurse Joanne came in, they had an argument, and then she yanked him out of class. Gil takes a look at the piece, which is ringed in grooves not unlike those found on an LP. The art teacher comments, "Adam's work is very provocative." "It speaks to me," Gil replies.
Back in the lab, Sara's asking Gil, "Acoustic archeology?" Gil explains, "In the sixties, experiments were done on clay pots and painted canvas. Scientists were able to ferret out sounds captured during the creative process in the clay and paint." "Trippy," Sara comments. Sofia, who's bothered to show up for CSI Science Minute, explains, "It's actually not that far out. In the old days, the first gramophone recordings were made by taking the vibrations of sound and cutting them into wax cylinders while they were turning. Based on the frequency and intensity of the sound, the stylus cut into the wax, creating distinct variances of depth and width. For playback, a mechanical transducer vibrated along a groove, generating a current which, when amplified, turned into sound."
Sara takes all this in with an expression best summed up as "Bitch, step offa my turf." But the point to the mumbo-jumbo is that we had to have some sort of semi-plausible explanation for explaining how the sounds "Robbie" and "my angel" get captured in the clay. And remember, Adam's creepy mother used to write him letters in which she called him "my angel." So…Creepy Nurse Joanne is Adam's mother.
Incidentally, Mr. Sobell and I both called this before Adam attacked Sara.
We've now got Creepy Nurse Joanne in the interrogation room. Sara points out, "The brush in Adam's room was fresh enough to get a DNA profile. It came back female. We tested it against your cigarette butt. It matched." "Adam liked it when I brushed his hair," Creepy Nurse Joanne protests. "I'll bet he did," Brass deadpans. Oh, Brass, you make my heart go pitter-pat. Sara jumps back in with, "You were lying about giving Robbie lipstick. You have seven out of 13 alleles in common with your patient, Adam Trent." Brass picks up a letter and adds, "Your dearest angel. Okay…Joanne McKay, registered nurse, licensed by the Nevada board of nursing 1978, married Howard Trent 1980. The board requires you to get a new certificate when you get married. I guess you never complied." That seems like the least of her legal problems right now. Creepy Nurse Joanne protests that she's always gone by her maiden name. Brass cracks, "I guess that makes it less embarrassing to check into a motel with your son." There's an awkward pause, and Brass says insincerely, "Oh, I'm sorry. You checked into a psycho ward instead." Creepy Nurse Joanne protests, "He needed me." Sara asks brightly, "For what? To destroy his ego? To fill him with guilt? To make him hate himself so much, he would take his own life just to be free of you?" Creepy Nurse Joanne assumes a martyred expression and says, "You have no idea what goes on between us." And I don't want to. Brass snorts, "Cut the umbilical cord, okay? Six months ago, your letters start coming back unanswered. No more communication with Little Lord Fauntleroy. So you applied to Desert State. They were desperate for nursing staff. They didn't perform any background checks whatsoever." Cut to a flashback where Dr. Dino introduces the new nurse and Adam very quietly freaks out all, "Ooh, this is awkward. We used to date." Brass continues, "But it's tough to turn folies a deux into ménages a trois. N'est-ce pas?" Then we get a flashback to mother-son hair brushing hour. Sara twists the knife: "Even tougher that your son was cheating on you…with a man, no less." We then flash back to the fateful pottery argument, in which Creepy Nurse Joanne (or is that Jocasta?) instructs Adam to end it with Lucielle Two -- I mean, with Robbie.