Fun read, but terrible ethics and lots of violence.
Plot
When Amy and Dan Cahill's grandmother passes away, her will brings to light a race to find 39 clues that, together, will change the world. Amy and Dan must compete against different members of their very large Cahill clan. The first adventure takes them to the catacombs under Paris to find the first clue among the bones of the departed.
Morality
There is little morality in the book. The Cahill family members burn down houses, set off concussion bombs (intended to stun people), try to bury each other alive, etc. There is a great deal of fighting not just among the competing teams but among the siblings. Everyone is cutthroat and determined to win at any cost.
The children run away from their guardian with their Au Pair. Their guardian hates the responsibility of the children and calls social services to remove them from the home once their grandmother passes away.
Spiritual Content
Very little spiritual content.
Violence
A great deal of violence! There is always someone who is trying to stop Amy and Dan or do away with them completely. Also, there is the theme of the skeletons in the catacombs.
Drug and Alcohol Content
The use of poison tipped darts, etc.
Sexual Content
None.
Crude or Profane Language or Content
See morality.
Conclusion
It is a very interesting book. It is full of clues and secret messages, danger and surprise. However, I would be hesitant to let young readers near this series due to the extreme violence and disregard for any rules/ethics etc.