Rex took a good look around before getting on his bike. “I just hope it stays quiet. I wonder where all those darklings came from. I had no idea there were so many big ones.”

Dess nodded. “I’ve been thinking about that. Want to hear a theory?”

“Sure.”

“Okay. Darklings look like panthers or tigers, right? Except when they get all freaky like they were last night.”

“Yeah. The lore says they’re related to the big cats—lions and tigers—like we are to apes.”

“Okay,” Dess continued. “Well, my lore, which would be the Discovery Channel, says that cats spend a big percentage of the day sleeping. Take lions. They sleep twenty-two hours a day, lolling around, tails twitching to keep away flies, maybe yawning out the occasional territorial roar, but basically semiconscious.”

“Twenty-two hours of sleep a day? That sounds like my dad’s cat.”

“So that leaves just two hours awake, right? For one of those hours they do kitty maintenance: lick themselves, play-fight other members of the pride, whatever. They hunt for only one hour out of twenty-four.”

Rex whistled. “That’s the life. A five-hour workweek.”

“Seven,” Dess corrected. “They don’t get weekends.”

“Harsh.”

“So here’s the thing. If darklings are like big cats, then they probably only hunt for one hour a day.”

“Sure,” Rex agreed.

“But what’s a day for a darkling?”

Rex pondered as he rode, recalling his precious lore. “Well, the darklings only live one hour in twenty-five, the secret hour. They’re frozen for the rest, like regular people are frozen during the blue time. So it takes them twenty-five of our days to live a single day in their life. That’s part of why they live so long.”

“Right,” Dess said. “So, a darkling probably sleeps for twenty-three of our days in a row.”

Rex’s bike wobbled. She could tell he hadn’t thought this through before. She shook her head. People’s lives would be so much simpler if every once in a while they bothered to do the math.

“And that means,” he said slowly, “that they only hunt about once a month. Like a werewolf in mythology.”

“Exactly. That must be where the whole full-moon thing comes from. Except darklings hunt once every 3.571429 weeks, not every four. But who’s counting? In any case, this means that there’s a lot more darklings than we thought, because most of them are sleeping most of the time. We’ve only seen the tip of the iceberg. For every one hunting, another twenty-three are asleep.”

Dess let Rex soak in this information for a while.

Finally he said, “So the question isn’t, ‘Where did they all come from?’”

“Right,” she answered. “The question is, ‘Why did they all wake up?’”

When Jessica answered the knock on her window, she looked disappointed to see them.

“Expecting someone else?” Dess asked.

“Kind of,” Jessica said quietly.