Cassie was sitting in third-period history debating between (a) the Continental Congress and (b) the House of Representatives on her pop quiz, when a hall monitor came to the door and handed Ms. Darby a pink slip of paper.

"Laurel," Ms. Darby said. "Mr. Boylan wants to see you in his office right away."

Cassie's head shot up. She couldn't allow Laurel to be alone with the principal. He was a witch hunter, and Laurel had been marked.

Laurel looked at Cassie and then back at Ms. Darby. "But I haven't finished my test yet."

"You can make it up after school," Ms. Darby said. "The principal wouldn't call you out of class unless it was important."

Laurel hesitated.

"Go on." Ms. Darby pointed to the doorway. "If you're in trouble for something, standing here and keeping him waiting surely won't help matters any."

"Yes, ma'am," Laurel said.

Cassie watched her fearfully gather her books. What could she do to stop her?

Laurel handed her exam in to Ms. Darby and obediently followed the monitor out the door, glancing over her shoulder at Cassie one last time.

There were no other Circle members in class, so it was up to Cassie to do something. One way or another, she had to get herself into the principal's office. Laurel's life could be at stake.

Cassie quickly scribbled in the remaining empty blanks on her exam, and then rushed up to the front of the room.

"I'm done, Ms. Darby." She held her side and bit her lip. "And I'm not feeling so well. May I go to the nurse?"

Ms. Darby eyed Cassie, trying to discern if she was faking.

Cassie swallowed hard, cleared her throat, and leaned forward like she might puke right on Ms. Darby's desk.

"Go," Ms. Darby said, and Cassie bolted for the hallway.

She ran the whole way, ignoring multiple commands from teachers telling her to slow down, and arrived at the principal's office panting. Immediately, she could feel an energy in the air - something dark and morose. The door to Mr. Boylan's office was closed.

"Hi there, Cassie. What can I do for you?" asked Mrs. Karol, the perpetually rosy-cheeked office secretary.

"There's an emergency," Cassie said, catching Mrs. Karol by surprise. "In the gymnasium. A fight or something, I'm not sure, but people were screaming for someone to get the principal right away."

"Not again." Mrs. Karol scooted off her seat and hurried over to the principal's door. She knocked on it anxiously while turning the knob to let herself in.

"Sorry to interrupt," she said, "but I think we've got a brawl on our hands, down in the gymnasium."

Mr. Boylan jerked backward, away from Laurel, the moment the door opened. He patted down his salt-and-pepper hair and straightened his gray suit. "I'm a little busy here."

He backpedaled to his desk and grabbed a pen and manila folder, presumably to appear more official. "And how many times have I told you, you can't just barge into my office like that."

"Don't you snap at me," Mrs. Karol said, with her bright smile fully intact. "It's not my fault your students behave like wild animals." She entered the room and took him by the elbow of his finely tailored jacket. "Now hurry up. You're the only one who can handle this."

Cassie spotted Laurel seated across from Mr. Boylan's large oak desk. She waved at her to try to catch her attention, but Laurel was entirely oblivious to everything going on around her. She was as pale as a ghost, and her eyes were focused on an invisible spot in front of her.

With a huff, Mr. Boylan followed Mrs. Karol toward the gymnasium. "Let's make this quick," he said, and then noticed Cassie for the first time.

"I won't be long," he called out to Laurel, while focusing directly on Cassie. "We'll pick up right where we left off when I return. You can count on it."

It sounded like a threat aimed at them both. Cassie shuddered at the thought of what she might have walked in on if she'd arrived only a few minutes later.

Laurel still hadn't moved a muscle, even after the principal and Mrs. Karol were out of sight. Cassie ran to her and shook her by her thin, delicate shoulders. "Are you all right? What did he do to you?"

Laurel's face slowly came back to life, and she finally noticed Cassie standing there. "We have to get out of here," she said, and leapt from her seat to run for the door.

Cassie grabbed her by the hand and led her down the hall to the science wing. "Steer clear of the gymnasium," she said, as she maneuvered Laurel in the opposite direction. It was only a matter of time before Mr. Boylan realized there wasn't any fight. "We need a place to hide. At least until the bell rings."

Down the wing, there was an unlocked supply closet. Cassie guided Laurel inside and closed the door behind them.

"It smells like formaldehyde in here," Laurel said.

Cassie didn't have the heart to alert Laurel, an avid animal lover, to the jarred pig fetus directly behind her. "You're right, it does," was all Cassie said, and then pulled Laurel in for a hug. "I'm just glad you're okay."

Among countless shelves of glass beakers and safety goggles, Laurel let herself cry and explained how Mr. Boylan had been interrogating her, trying to find out information about her friends.

"He was asking me about everyone in the Circle by name," Laurel said. "And he was asking about our families. He knows we're all witches, Cassie, and he wants to mark every one of us."

Cassie was gradually putting the pieces together. "Then we absolutely can't perform magic until we figure out how to stop him."

Laurel's eyes welled up with tears again.

"You're okay now," Cassie assured her. "And you're not alone. We're going to figure out a way to save you. I promise."

"How? We are in over our heads, Cassie. This isn't like anything we've ever faced before." Laurel started to cry so furiously Cassie was afraid someone in the hallway would hear them. "I don't want to die," she said.

"Shh. Nobody is going to die." Cassie lowered her own voice to a whisper. "I've been talking to my mom about my father. Just last night in fact. And I'm learning things, Laurel. Ancient things that will help us."

Laurel's sobbing quieted and she wiped the tears from her rosy cheeks. "Really?" she asked.

"Really. When my father was young he saved a friend of my mother's who had been marked. I know it can be done."

"And you think you can figure out how he did it?"

"I know I can," Cassie said. She said everything she could think of to try to help Laurel calm down, but in her mind she feared they were running out of time. She had to do something about this - and her father's book - before the hunters picked them off one by one.