They are different ages, genders, ethnicities, but there are commonalities among them: They all wear the same hospital smock. They all have a hand cuffed to the safety bar of the bed. And they all waver in place, as if fighting an invisible wind, and stare blankly out at Annabelle and Isaac. Every few seconds, one of them will bark out a cough, a phlegm-thickened rattle. Many have thick gray trails of mucus running out of their eyes, their noses, their mouths, and even their ears.

Dr. Johnson says, “They all came in screaming. Gnashing their teeth. Thrashing against their restraints. But as soon as we get them in here, they calm down.”

“So there’s some sort of stabilization as a result of proximity?” Isaac says. “They’re among familiars.”

They watch as one patient, and then another, then another and another and another—all of them—lift a hand. They extend their index fingers and bring them to their mouths as if to say, Shh.

Then the fingers sneak between their lips. Their teeth snap down, biting as hard as they would on a stalk of celery. Skin breaks; blood blooms. And with the blood they begin to draw on the glass walls of their rooms. They all crouch together, beginning at the floor, working their way up, and curling down again, creating a slow series of circles that spiral inward and take up the entirety of each window. It is a monstrous choreography, a strange ballet.

“Go on,” Annabelle says and nudges Isaac forward. “Do your work.”

Isaac takes a short walk around the ward, listening to them cough, studying the ciphers on the glass more carefully. When he returns to the nurses’ station, Dr. Johnson asks, “It’s got something to do with that damn comet, doesn’t it?”

Isaac says, “The sky laid the seeds five years ago. Now the rains have awakened them. In Puget Sound and the Olympic Peninsula, we’re dealing with a sudden proliferation of new plant and fungal life.”

“Including yourself.”

“Including myself.”

“But you’re not one of them.”

“No, I am most certainly not.”

“Then what are you?”

“You don’t have to answer that,” Annabelle says.

“It’s okay,” Isaac says, though he takes his time responding. “There are examples of lichens that seem to grow with the specific expectation that birds will harvest them and make them into a nest.”

“Okay?”

“They’ve learned how to work with others to make a new home. I think that’s what we’re seeing right now with a lot of the alien flora. It’s been waiting, learning, adapting. It’s testing out this new environment and trying to find the best way to grow in it.”

“Are we even talking about science right now?” Dr. Johnson says. “Because this sounds like the stuff of myths. Green men and gray men and the like.”