Henry Allen’s dog is missing and he thinks it’s been eaten by a dragon! On the night the dog disappeared, Mr. Allen swears he saw a huge dragon slither into the sea caves beneath his cliff-top house. Could Mr. Allen really have seen a dragon? The Three Investigators doubt it, but they’re determined to find the missing dog. That means exploring those dark, dangerous caves. And whether or not Mr. Allen’s dragon is real, something terrifying and deadly is lurking there!–Back cover