Elizabeth Wakefield and her best friend Amy Sutton have big plans for the holiday weekend, including a fabulous party, a family barbecue, and the chance to see a dreamy deejay broadcast live from Sweet Valley Mall.
But the weekend gets off to a surprising start when Amy's pen pal from San Francisco shows up unexpectedly. Samantha Williams seems every bit as nice as her letters until Amy introduces her to the Unicorns. Suddenly, the popular girls can't get enough of Sam and her stories, and Amy begins to feel left out. Why hasn't Sam ever told her about all those wonderful things she's done? Elizabeth and Jessica have a feeling she's making it all up. But will Elizabeth be able to stand by while her twin plans a coldhearted plot to uncover the truth?

Elizabeth led Amy to a circle of chairs where they could continue their conversation in private. "I've been talking to Jessica, and she says that Sam is always bragging."
"She sure is. You should have heard her yesterday at lunch. She even said her family has a house in Hawaii."
Elizabeth leaned forward. "Well, Jessica thinks Sam is making up most of her stories."
"I had the same suspicion," Amy admitted. "I even asked Sam why she hadn't even written me about all the stuff she's been talking about, but she just said she had forgotten to."
"Jessica is going to prove that Sam is lying," Elizabeth said bluntly.
Amy's eyes opened wide. "How?"
Briefly Elizabeth explained.
"Wow. That would be great," Amy said, her eyes glowing. She glanced over in Sam's direction. "As far as I'm concerned, Samantha Williams deserves to be put in her place."

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