Ivy Vega and her best friend, Sophia Hewitt, hustled through the oldest cemetery in Franklin Grove on their way to school Monday morning. The grassy path, stiff with frost, crunched loudly beneath their heavy boots, and Ivy pushed her hands into the pockets of her full-length, black down jacket to keep them warm.

I'm going to miss this old graveyard when I move to Europe, Ivy thought. Even though it was still a little dark, in the distance she could make out the low silhouette of her boyfriend's family crypt, where she and her friends had spent so much time hanging out. Outside the cemetery gates, the lights of nearby houses twinkled.

"Such a killer party!" Sophia exclaimed, interrupting Ivy's thoughts. It seemed like forever ago, but on Saturday, Ivy's human twin, Olivia, had been initiated into the vampire community, and they'd had a little celebration. "You must be seriously excited," Sophia went on, "that Olivia knowing about vampires isn't a secret anymore. It's all over the Vorld Vide Veb."

Ivy pressed her mouth down into her black knitted scarf and exhaled, warming her neck. That's not the only thing that isn't a secret any longer, she thought. "Sophia," she said aloud, "there's something I have to tell you."

Olivia Abbott was met by a hot blast of indoor air as she opened one of the huge oak front doors of Franklin Grove Middle School. Scanning the lobby, she pulled off her hat and swung it around by one of the pink pom-poms that hung from its earflaps. She jumped up and down to get the cold out. Olivia had worn her cheerleading uniform for a school spirit assembly, but even with leggings, she felt like an icicle.

Where are you, Camilla? Olivia thought as she hopped from foot to foot, keeping her eyes peeled for her friend. I have huge news!

The door to the outside swung open, and Olivia looked over eagerly. Unfortunately, it was just Charlotte Brown, Olivia's snotty cheerleading captain. She was wearing fluffy white earmuffs.

"Hi, Charlotte," Olivia said, unable to keep the disappointment out of her voice. Charlotte let the door swing shut behind her, but her cheerleading cronies, Katie and Alison, hurried in on her heels. They were wearing fluffy earmuffs, too.

"Oh, Olivia, I'm so totally cold!" Charlotte whined.

"We're cold, too!" said Katie and Alison, who had a talent for always thinking the same thing as Charlotte.

"Then you'd all better get inside right away and warm up!" Olivia said, switching on her smile. They skipped past without another word.

One person after another trickled into school, and every time the door to the outside opened, Olivia's heart leaped. Finally she caught sight of Camilla's bouncy blond curls.

"Camilla!" Olivia called.

"Hey," Camilla said, her face breaking into an easy smile when she saw Olivia. "Sorry I'm a little late. You sounded so excited on the phone last night. What's up?"

Olivia grinned. "Only the biggest news of my entire life!"

Camilla looked at her skeptically. "Bigger than finding out you have a long-lost twin sister?"

Olivia wrinkled her nose; Camilla had a point. Olivia and Ivy hadn't even known they each had a twin until Olivia's first day of school in Franklin Grove a few months ago. Come to think of it, the whole my-sister-is-a-vampire thing was big news, too, but of course Camilla didn't know anything about that. Olivia was one of the only humans in the world who did.

"Just as big," Olivia decided, pulling Camilla behind the enormous potted ferns in the corner of the lobby.

Olivia took a deep breath. "You can't tell anyone," she said. "Promise?"

"Promise," Camilla said solemnly. "Just tell me already!"

"I am telling you," Ivy protested.

"No," Sophia said, "what you're doing is trying to tell me. So far you're just sighing a lot."

Ivy sighed again, sending a tiny cloud into the cold air. "I still can't believe it," Ivy murmured by way of explanation.

"Ivy," Sophia said sternly, "I'm freezing my fangs off here."

"You don't have fangs," replied Ivy, peering around the cemetery to make sure no one else was lurking nearby. "You file them like the rest of us."

"It's an expression," Sophia said, her voice rising with frustration. "Now tell me your big revelation!"

"I found... " Ivy gulped. "Olivia and I found out... "

Sophia stared at her impatiently.

"Who my real father is," Ivy blurted at last.

"Really?" Camilla cried, her eyes widening. Olivia nodded, biting her lip to contain her smile. "I'm so happy for you!" Camilla threw her arms around Olivia, accidentally knocking one of the ferns. Olivia giggled.

"I knew you and Ivy would find some answers if you kept looking," Camilla said proudly.

Olivia had to admit that their perseverance had paid off. She and her sister had been trying to solve the mystery of who their parents were since they'd first realized they were twins.

"Thanks, Camilla," Olivia said, hugging her again. "I wanted to tell you in person."

"So who is he? Who's your dad?" Camilla asked, her voice bursting with curiosity.

Olivia pursed her lips, savoring the moment.

Camilla read her face. "I knew it!" she squealed. "It's a celebrity! I always thought you two had George Clooney's nose!"

"Nope," Olivia shook her head coyly. "Even better."

"Antonio Banderas?" Camilla whispered in awe.

"Well then, who?" Sophia said excitedly, wrapping her arm around Ivy's as they made their way out of the cemetery.

Ivy's long dark hair fell in front of her face. "He's, uh, his name is... Karl Lazar," she sputtered. Why am I having so much trouble telling my oldest friend the whole story? Ivy wondered. Somehow, this was just too unbelievable to blurt out.

"Lazar?" Sophia repeated. "You mean that Transylvanian vamp aristocrat who fell for a human?"

Ivy nodded dumbly.

"That's amazing! Do you know if he's still alive?" Sophia asked.

"Oh, he's alive," Ivy said.

"How do you know?" Sophia pressed.

"He's been in hiding for the last thirteen years," Ivy answered.

As Franklin Grove Middle School came into view in the distance, Sophia's steps slowed. "Ivy, why do I think there's something you're not telling me?"

Ivy smiled shyly, relieved that her friend knew her so well. "Because there's something I'm not telling you?" she replied.

As Sophia searched her face, Ivy took one last deep breath. She pushed her hair out of her eyes.

"My dad is my dad," she announced, the words rising into the air like smoke.

Sophia looked at her blankly.

"My dad is my real dad," Ivy clarified.

Sophia did a double take. "You mean your father, Charles Vega, who you've known for your entire life... "

"... is Karl Lazar," Ivy finished.

Sophia peered at her in disbelief. "You're biting my neck, right?"

Ivy grinned. "No fangs, remember?"

"But why would Mr. Vega pretend to be Ivy's adopted dad when he's actually her real father?"

Camilla asked.

"We don't know." Olivia frowned. "Maybe because he didn't want Ivy to know she had a twin."

"But why not?" Camilla pursued.

All Olivia could do was shrug. She wanted to tell her friend everything she and Ivy had learned: about how their father was a vampire while their mother was a human and that he'd separated the twins after their mother had died. But she'd taken a Blood Oath never to violate the First Law of the Night, which meant she must never reveal the existence of vampires to a nonvampire. It was a bummer, because Camilla was supersmart, and Olivia thought maybe she'd have some ideas about why Mr.Vega had done what he had.

Ivy and Sophia climbed the school steps. "Does your dad know you know?" Sophia asked.

Ivy shook her head. "Olivia and I talked about it and agreed that we're not telling our parents yet. Olivia's mom is going to flap like a bat when she finds out the truth. And my dad's already utterly uncomfortable around Olivia."

They went inside and were walking across the lobby when Ivy heard someone call her name in a stage whisper. She looked around, but none of the students milling around the lobby was looking her way.

"Ivy! Sophia!" the voice came again.

"I think that fern is calling us," Sophia murmured, pointing to the corner. The two of them walked over. Suddenly, a pink-nailed hand reached out and pulled Ivy behind the greenery.

Olivia was huddled back there with Camilla. "Did you tell her?" Ivy and Olivia asked each other at the same time. They nodded to each other and then had a big group hug.

"Congratulations on finding your father."

Camilla grinned at Ivy.

"Can you believe that, this whole time, their real dad's been right in front of them?" Sophia said excitedly to Camilla, who shook her head in disbelief.

"You guys can't tell anyone," Olivia said seriously.

"Not even Brendan?" asked Sophia.

"Except Brendan," Ivy replied. She was planning on telling her boyfriend after first period.

She wanted to tell him in the science hallway, where he'd first asked her out. She'd made him a card, thanking him for all his support during her search for the truth.

"Must be a big secret," said Sophia with a smirk. "After all, we're hiding behind a fern!"

For once, Olivia didn't smile. "Ivy and I are declaring a state of emergency; she and her dad are supposed to be moving to Europe."

"He's your dad, too," Ivy reminded her gently.

Olivia nodded. "Right," she agreed, thinking that that was going to take some getting used to.

"And we've got less than ten days to convince him not to move."

"We're not going to let ourselves get split up again," Ivy declared bravely.

"And I'm not losing my biological father now that I know who he is," Olivia added.

Camilla and Sophia had both snapped to attention. "How can we help?" Camilla asked. "Do you really think your dad might change his mind?" Sophia wondered.

"He has to," Ivy answered.

"We're going to come up with something that will make it impossible for him to leave," said Olivia.

"Something so killer," Ivy put in, "that he'll be dying to stay."

"Like what?" asked Sophia.

Ivy and Olivia looked at each other doubtfully.

"That's what we're hoping you'll help us figure out." Ivy smiled weakly.

The four girls stared at one another.They were still standing there, deep in thought, when the bell for first period rang.

"Huddle," Olivia called, and the four of them gathered close. "We'll meet at lunch to come up with a plan," she said.

Everyone nodded. Then Olivia prompted everyone to put a hand in the middle. "Franklin Grove or bust," she said.

"Franklin Grove or bust!" Ivy and her friends repeated in unison, their hands pumping and then rising into the air like a starburst.