Kurt and Willie have returned from their adventure at Emerson's Cove only to find themselves thrust into one of the most important rescues of their lives.They find Mrs. Hendicott missing! They find a cryptic message written in blood! They find a skeleton key in a secret hiding place. How do the clues fit together? And, will they find Mrs. Hendicott in time?Book Six in the Young Detectives' Mystery series is a gripping mystery of suspense and danger that takes Kurt and Willie back to Pirate's Cove!