Book 8 of 17 in the bestselling standalone middle grade mystery series! ★★★★★ Over 4,000 five star series reviews/ratings on Amazon and Goodreads Are you up for a thrilling adventure? While visiting a village on the French coast, the Mystery Kids hear about a sea monster that haunts the nearby cove and decide to investigate. Follow the children as they are trapped in a flooded room, explore a desolate island, escape in a canoe, swim in foggy waters, survive an earthquake, and more! Book 8 in the Mystery Series, this adventure novel is set in 1950's Britain and will suit anyone who enjoys Nancy Drew, the Hardy Boys or the Famous Five.