Kelsey told Hannah. “I don’t own a gun,” Hannah said. “And I’m not giving you one—not right now, anyway. But you need to learn how to use one in case there’s ever a need.” Once, Hannah thought, she would have argued. She’d never been fond of guns—not even spear guns. She dived for pleasure, to see fish, not shoot them. Not that she didn’t like to eat them, too; she just wanted them on her plate, a nice filet, or maybe some sushi. “All right,” she agreed. “This is my service weapon,” Kelsey told her, placing her gun on the table. “It’s a Glock 19. It uses a magazine. Right now it’s loaded, but I’m going to unload it. To do that, you push the little button right here, on the side, by the handle.” She demonstrated. The magazine fell into her hand. “Okay, you can’t be certain at this stage that there isn’t a round still in it—that it’s really unloaded—so you bring the slide back.