Murphy's breath escaped in something like a hiccup. She opened her eyes, a mix of anger and wary amusement easing into them in place of the fear. "You do realize I'm holding a gun, right?"

"You're fine. Hold your hand still." Though her fingers still trembled a little, the wild, panicked spasms had ceased. I wrapped the twist of hair and thread around her finger.

Murphy kept on peering through the mist, her gun steady. "What are you doing?"

"Enchantment like that mist is invasive," I said. "It touches you, gets inside you. So I'm setting you up with a defense. Left side is the side that takes in energy. I'm going to block that mist's spell from going into you. Tie a string around your finger so you won't forget."

I tied the string in an almost complete knot, so that it would need only a single tug to finish. Then I fumbled my penknife out of my pocket and pricked the pad of my right thumb. I looked up at Murphy, trying to clear my thoughts for the spell.

She regarded me, her face pale and uncertain. "I've never really seen you, you know. Do it. Before."

"It's okay," I told her. I met her eyes for a dangerous second. "I won't hurt you. I know what I'm doing."

She lifted the corner of her mouth in a quick smile that made her eyes sparkle. She nodded and returned to peering out through the mist.

I closed my eyes for a moment and then began gathering my focus for the spell. We were already within a circle, so it happened fast. The air tightened on my skin, and I felt the hairs along my arms rise as the power grew. " Memoratum," I murmured. I tied off the improvised string and touched the bead of blood on my thumb to the knot. " Defendre memorarius."

The energy rushed out of me and into the spell, wrapping tight around the string and pressing against Murphy. A wave of goose bumps rippled up her arm, and she drew in a sudden sharp breath. "Whoa."

I looked at her sharply. "Murph? You okay?"

She blinked down at her hand, and then up at me. "Wow. Yeah."

I nodded, and took my pentacle out of my shirt. I wrapped it around my left hand, leaving the five-pointed star lying against my knuckles. "Okay, we're pushing our luck enough. Let's hope this works and get the hell out of here."

"Wait, you don't know if it will work?"

"It should work. It ought to. In theory."

"Great. Would it be better to stay here?"

"Heh, that's a joke, right?"

Murphy nodded. "Okay. How will we know if it works?"

"We step outside the circle and if we don't drift into Lala Land," I said, "we'll know it worked."

She braced her charmed hand on the butt of her gun. "That's what I love about working with you, Dresden. The certainty."

I broke the circle with a shuffle of my foot and an effort of will. It scattered with a pressured sigh, and the grey mist slid forward and over us.