内容简介：
THIRTEEN-YEAR-OLD NICK BARRETT was startled to see a harbor seal swimming close to the Cape Cod shore. But when the seal suddenly vanished in a crashing wave and an oddly dressed boy named Ethan Kemp washed up on the beach, Nick's summer vacation changed in an instant. Why did Ethan seem so very different than Nick and his friends? What was his connection to the seal? And why did he have no memory of his past? Back in Nick's hometown of Sudbury Massachusetts, Ethan and his new friends try to solve the mystery of his past. They soon find themselves drawn deeply into a centuries' old puzzle involving a blind hermit, encounters with Babe Ruth and Henry Ford, an evil puppeteer who seeks to control their thoughts, and a crystal pendant whose secret is so powerful that the only solution may be to return to the past to keep it hidden forever. The Crystal of Dreams is a story of time travel and friendship spanning colonial and modern times.