At last he let her go. He moved to take over pushing Little Pete, seeming to need something physical to do.

“E.Z.’s dead,” he said without preamble. “I was touring the fields with Edilio. Me, Edilio, and Albert, and E.Z. along for entertainment. You know. No good reason for E.Z. to even be there, he just wanted to ride along and I said okay because I feel like all I ever do is say no, no, no to people, and now he’s dead.”

He pushed the swing harder than she’d been doing. Little Pete almost fell backward.

“Oh, God. How did it happen?”

“Worms,” Sam said dully. “Some kind of worm. Or snake. I don’t know. I have a dead one in there on the kitchen counter. I was hoping you’d . . . I don’t know what I was hoping. I figure you’re our expert on mutations. Right?”

He said the expert part with a wry smile. Astrid wasn’t an expert on anything. She was just the only person who cared enough to try and make sense in a systematic, scientific way of what was happening in the FAYZ.

“If you keep pushing him, he’ll be fine,” Astrid said of her brother.

She found the creature in a Baggie on the kitchen counter. It looked more like a snake than a worm, but not like any normal snake, either.

She pressed gingerly on the bag, hoping it really was dead. She spread waxed paper on the granite counter and dumped the worm out. She rummaged in the junk drawer for a tape measure and did her best to follow the contours of the creature.

“Eleven inches,” she noted.

Then she found her camera and took a dozen photos from every angle before using a fork to lift the monstrous thing back into the Baggie.

Astrid loaded the pictures onto her laptop. She dragged them into a folder labeled “Mutations—Photos.” There were dozens of pictures. Birds with strange talons or beaks. Snakes with short wings. Subsequent pictures showed larger snakes with larger wings. One, taken at a distance, seemed to show a rattlesnake the size of a small python with leathery wings as wide as a bald eagle’s.

She had a blurry photo of a coyote twice the size of any normal coyote. And a close-up of a dead coyote’s mouth showing a strangely shortened tongue that looked creepily human. There was a series of grotesque JPEGs of a cat that had fused with a book.

Other photos were of kids, most just looking normal, although the boy called Orc looked like a monster. She had a picture of Sam with green light blazing from his palms. She hated the picture because the expression on his face as he demonstrated his power for her camera was so sad.

Astrid clicked opened the worm pictures and used the zoom function to take a closer look.

Little Pete came in, followed by Sam.

“Look at that mouth,” Astrid said, awestruck. The worm had a mouth like a shark. It was impossible to count the hundreds of tiny teeth. The worm seemed to be grinning, even dead, grinning.

“Worms don’t have teeth,” Astrid said.

“They didn’t have teeth. Now they do,” Sam said.

“See the things sticking out all around its body?” She squinted and zoomed in closer still. “They’re like, I don’t know, like minuscule paddles. Like legs, only tiny and thousands of them.”

“They got into E.Z. I think they went right through his hands. Right through his shoes. Right through his body.”

Astrid shuddered. “Those teeth would bore through anything. The legs push it forward once it’s inside its victim.”

“Thousands of them in that field,” Sam said. “E.Z. goes in, they attack him. But me and Albert and Edilio are outside, we haven’t stepped into the field, and they don’t come after us.”

“Territoriality?” Astrid frowned. “Very unusual in a primitive animal. Territoriality is usually associated with higher life-forms. Dogs or cats are territorial. Not worms.”

“You’re being very calm about all this,” Sam said, almost but not quite accusingly.

Astrid looked at him, reached with her hand to gently turn him away from the horrible image, forcing him to look at her instead. “You didn’t come to me so I could scream and run away and you could be brave and comforting.”

“No,” he admitted. “Sorry. You’re right: I didn’t come to see Astrid my girlfriend. I came to see Astrid the Genius.”

Astrid had never liked that nickname much, but she’d accepted it. It gave her a place in the dazed and frightened community of the FAYZ. She wasn’t a Brianna or a Dekka, or a Sam, with great powers. What she had was her brain and her ability to think in a disciplined way when required.

“I’ll dissect it, see what I can learn. Are you okay?”

“Sure. Why not? This morning I was responsible for 332 people. Now I’m only responsible for 331. And part of me is almost thinking, okay, one less mouth to feed.”

Astrid leaned close and kissed him lightly on the mouth. “Yeah, it sucks to be you,” Astrid said. “But you’re the only you we have.”

That earned her a bleak smile. “So, shut up and deal with it?” he said.

“No, don’t ever shut up. Tell me everything. Tell me anything.”

Sam looked down, unwilling to make eye contact. “Everything? Okay, how about this: I burned the body. E.Z. I burned the mess they left behind.”

“He was dead, Sam. What were you supposed to do? Leave him for the birds and the coyotes?”

He nodded. “Yeah. I know. But that’s not the problem. The problem is, when he burned? He smelled like meat cooking, and I . . .” He stopped talking, unable to go on. She waited while he mastered his emotions. “A dead sixth grader was burning, and my mouth started watering.”