In this fifth book in the Key Mystery Series, Mandy and Nick are joined by Christianne and Noah on a camping trip in a California redwood forest. While panning for gold at a stream, mysterious things begin to happen. Their equipment disappears and they find gigantic footprints on the path. Is the dark figure lurking in the woods the legendary Bigfoot? After finding a key in a hollow tree called the Old Prospector, the children set out to find what...