Read a crime case, assemble a glowing puzzle, solve the case. During a dive into the sunken city of Submaris, the three ??? are pursued by strange shadows. Is a monster lurking here? The detectives must solve the mystery, and players can help them: First, read the thrilling short story, then piece together the crime scene and find the hidden clues. The included mysterious treasure map assists children in solving the exciting case. A cool puzzle challenge for aspiring detectives. Contents: 150-piece puzzle (size: 48 x 36.5 cm), 2 gadgets (treasure map + sticker sheet), 20-page guide with an exclusive short story and solution section.