“No!” I stepped in front of her as frigid air whooshed from the extinguisher’s nozzle like an icy jet engine. It shouldn’t hurt our books, but I had no idea what it would do to a fire-spider. I held my breath and squeezed my eyes shut. I heard books and paperwork flying behind me. The instant the stream died, I reached out blindly to yank the extinguisher away.

My eyes watered. I had to stop myself from rubbing them, which would only make the irritation worse. White powder covered my shirt and hands.

“He’s still burning!”

I glanced at Smudge. As the chemicals from the fire extinguisher dispersed, Smudge’s flames flared even higher, taking on an orange tinge. All eight eyes glared up at Mrs. Trembath with what I could only describe as pure arachnid loathing.

Mrs. Trembath returned to the doorway to fetch her cane, which she raised in both hands like a samurai sword. “At least put the poor thing out of his misery.”

“He’s not burning. He’s . . . bioluminescent.” I doubted Mrs. Trembath weighed more than a hundred pounds soaking wet, but she had raised five kids, and could probably take on an entire wolf pack through sheer cussedness. Unfortunately, the last time I had seen Smudge this spooked, the threat had been far worse than wolves.

“Isaac Vainio, you get out of my way and let me help that poor creature.”

Magic would have ended our standoff, but I was already pushing things by keeping Smudge. Even the smallest spell could get me hauled down to Illinois to explain myself to Nicola Pallas, the Regional Master of the Porters.

Instead, I folded my arms and said, “Smudge is fine, but I really need to take care of the furnace situation.”

“He’s not fine, he’s—”

“Are you questioning my authority?” I widened my eyes, hamming it up as much as possible. In a faux-military voice, I asked, “Are you aware that section six point two of the Copper River Library user agreement gives me the authority to revoke your library card, including Internet privileges?”

She lowered her cane. “You wouldn’t dare.”

I leaned closer and whispered, “A librarian’s gotta do what a librarian’s gotta do.”

We stared at one another for about five seconds before she cracked. With an amused chuckle, she jabbed a finger into my chest. “So why haven’t I ever seen him glow before?”

“Diet,” I said quickly. “He escaped last night and got outside. He must have gobbled down at least a dozen fireflies before I caught him.” I braced myself, praying she didn’t know enough about biochemistry to see through my rather weak excuse.

She backed down. “Maybe if you gave him real food instead of candy, he wouldn’t have to sneak out on his own.”