The Haunted Lagoon — Carolyn Keene

Louise and Jean Dana stare unbelievingly through the swirling mists in an isolated lagoon. Floating in mid-air is a full-rigged sailing ship! A moment later it vanishes.

Never before have the Danas encountered so eerie an challenging a mystery. To find the solution, they must locate a former sea captain who mysteriously disappeared from Chincoteague Island off the Virginia coast. During their search, of the neighboring islands, the two young sleuths are thwarted by a sinister enemy who resorts to desperate measures to prevent them from unearthing the truth.

Readers will share many thrilling adventures with the Danas as the young detectives and their friends pursue the baffling trail of clues that leads them to pirate treasure and a startling climax.