Mystery Masterpiece The Moonstone. An ancient and priceless piece of jewelry, the Moonstone, has been stolen. And it’s up to you to track it down! Investigate every person who was in the mansion at the time of the crime. To solve the mystery and catch the crook, in this Hidden Object game! Explore every room of the mansion to find valuable clues in Mystery Masterpiece The Moonstone, and return the jewel to its rightful owner.