Meanwhile, Petty is holed up in a tomb, polishing one of his ill-gotten medals. A guard walks in. Petty stabs him.
The next morning, Doc and Rebecca show up at the Presidio. Doc says Petty's original stash of mines was never found. Rebecca figures out in all of five seconds that the mines were hidden in the tomb.
Flashback. Lucy hands Petty a cup of hot tea, which he drinks gratefully. "Now that's how you treat someone when you want something, Warden," he says. Lucy calmly explains she drugged his tea. "Just a mild sedative to help you relax," she says. His facial expression goes, "Aw, shit." Lucy switches on a reel-to-reel recorder. She recites a list of his wartime accomplishments, like clearing several minefields by himself. His fellow soldiers were awarded medals, but Petty went without. She recounts how he then killed children, whom he calls "little soldiers." Lucy straps him into a chair and places electrical contacts at his temples. She places a rubber guard between his teeth. She gives him a short jolt of 55 volts, then removes the apparatus and guard. He starts singing something in Korean.
Later, Lucy plays the recording for Tommy Madsen, who is also a vet from the Korean War. She wants to ask him a few questions, but he has questions of his own. He wants to know why he spends so much time in the infirmary, for starters, and why they're taking so much blood from him. He makes a deal with her: He'll tell her what the song means, if she finds out why he's in the infirmary all the time. She agrees and he says the song is a lullaby. The Koreans used the lyrics to tell each other where they'd hidden the mines. They were in the fields where they once played. They had to stop in their tracks, for fear of walking on the mines they'd laid. Tommy says that one word in each line would point to a different location.
Alca-Hub. Hauser goes over Petty's old attack locations. The writing that looked like a poem is actually Petty's lullaby. The lyrics match up with Beard Field, Grace Cathedral and the Union Square Snow Festival. To figure out where Petty might be hiding the mines now, he looks up the lyrics of the song. Why is he just now doing this? It's been a day since the park thing, right? Anyway, it turns out there's a second stanza. One of the words is "pine," which Hauser types into the computer, instead of just remembering that Petty's attack was at Pine Street Park. "It matches," Hauser says when a map confirms this very obvious thing.