Cemetery. Rebecca and Doc break into the tomb, realizing that Petty broke out of the tomb, judging by the state of the lock. They further realize that this where Petty "came back." Down in the vault, they find where Petty has been painting his mines to blend in with their intended environments. He has a stash of sandstone-colored paint and chunks of rubber turf that Rebecca realizes is used all over the city in playgrounds and the like.
The bomb squad comes in to retrieve the mines. Psycho is with them and tells Rebecca about a ransom note sent to the city, demanding $651,000 in exchange for the location of the mines. Rebecca muses about that oddly specific number, then calls Hauser. He tells her to look for the word "windward," which he got from the lullaby, while he cross-references the word "sunset" with the sandstone paint Rebecca found and comes up with Sunset Beach. Not that he tells Rebecca this.
Rebecca and Doc bring the bomb squad to a park outside Windward Elementary. Psycho and the squad search and come up empty, so Rebecca sends them off to check other places that have the same turf. She calls Hauser to tell him he was wrong just as he's driving up to Sunset Beach. He tells her to stay at the park. For some reason, he still doesn't tell her where he is. It's so dumb and contrived. You know what else is dumb? When Hauser finds Petty planting his mines in the sand, he starts walking over to him. Hauser has a gun. He could easily incapacitate the guy from a safe distance, but no, he tromps right on up to him and steps right onto a land mine. Unfortunately, he doesn't explode, because he freezes as soon as he hears the mechanism click underfoot. Petty takes out a gun of his own and orders Hauser to hand over his gun and his phone. Also, I am slightly distracted by how horrible the green-screen background looks behind Petty.
Windward Elementary. It's night and Rebecca and Doc are still hanging around when Petty finally shows up. He's just starting to dig up a spot next to a playground slide when Rebecca pulls her gun on him. "You with the guy in the suit?" he asks, slightly surprised. She kicks him to the ground and cuffs him, then calls Hauser. She realizes something is horribly wrong when Hauser's phone starts ringing in Petty's backpack. "Where is he?" she asks. "He's somewhere he can ponder the error of his dumbass ways," Petty says. Or maybe he just says "tick-tick-tick!" with an annoying little smile.