Beau and Penny work the crime scene of a breaking-and-entering in a garage. Thumping leads them to a boy hidden inside a bin. No one knows who the nonverbal boy is. Josh joins Beau at the hospital to collect samples from the boy, whose bracelet reads, "Michael." Michael's DNA leads to identifying his mother Cara, who disappeared when  she was 16 years old. Cadaver dogs find Cara's body. Beau finds Michael's missing shoe at the burial site. Michael had been buried alive. Sonya believes that Cara had been held captive for years. Max receives a thank-you postcard from the mastermind behind the electro-shock killings, which Allie analyzes. The prints of Cara's high-school boyfriend, Samuel Daley, are on the letter she sent to her parents. But the gay Daley says Cara was his beard. He added that Cara had a secret, older boyfriend. Dr. Auerbach, Lynn Zobrist's psychiatrist, agrees to seek records for potential electro-shock victims. Michel freaks out when Beau offers him water. Penny uses local honey to pinpoint where the other missing girls may be buried. Jake Rooney, Cara's physics teacher, admits to being Michael's father. But he denies having anything to do with the abductions. Penny's locations from the honey lead to the discovery of Cara's dead baby. Cara and Michael were both submerged in cold water, which killed her. Beau finds a secret room in the recording studio of Cara's stepfather, Pete. Beau suggests that was where Cara and MIchael were held captive. The water main broke when Cara and Michael were trapped inside the soundproofed room. They tried to claw their way out. Pete claims he was just helping out the pregnant Cara. Pete was the baby's father. Beau turns in his evidence kit and insists on working only in the lab or he'll quit. Max gives in.