Beyond The Grave, written by Jude Watson, is the fourth book, and was released on June 2, 2009. It is about how Amy and Dan try to find an Ekaterina Clue left by the Ekaterina branch founder, Katherine Cahill. The setting of the story is Egypt, and in it, Dan and Amy learn about female pharaohs and goddesses. They discover how the Clues corrupt even the most brilliant Cahills and question Grace's love for them when they discover a secret Ekaterina stronghold at an Egyptian hotel that they were staying in, the Hotel Excelsior. Along the way, Grace's best friend, Hilary Vale, gives Amy and Dan several items from Grace. They discover that Grace is helping them find the next Clue. Amy and Dan work together with Alistair at the end of the book to reach the original location of the Clue, which is underwater. But they discover that the Clue has been stolen by the Madrigals. Alistair leaves Amy and Dan to look at books at his library. Then Amy and Dan realize that Grace didn't want them to go to the original location of the Clue, but to a store in Cairo. There, they receive a picture of a leaf. Then they go back to the Hotel Excelsoir, the hotel which is the location of the Ekaterina stronghold. There, they discover what the Clue is. The book ends with Amy and Dan finding the Ekaterina stronghold destroyed by the Madrigals, and the place where Amy and Dan are headed next is not revealed.