The 39 Clues Book 4 Beyond the Grave

A clue that Amy and Dan found in Book 3 makes them try and discover why there is such a strong rivalry between the Tomas and Ekaterina branches of the Cahill family. They end up in Egypt with their au pair Nellie and find themselves in danger once again as they search for clues in very famous historical tombs. They have trouble knowing who of their relatives they can trust and who they can't especially a friend of their grandmother's who seems to want to help them. Amy and Dan still fight all the time but they seem to work better as a team in this book. A message from their dead grandmother leads them to discover the clue which is a half gram of myrrh.