Philippa's parents work on a cruise ship. She helps them with their jobs. A new captain and his son are coming aboard for this trip. A Duchess and her nephews also are on this cruise. Philippa does not trust them especially as she notices how much they all watch her. She also likes mysteries. So she decides she will find out about them and about the captain's son who is a mass of contradictions.
I enjoyed this story. Philippa is very determined to solve the mystery even if it means she runs afoul of the cruise director and the captain. I wanted to slap the Duchess and her nephews. They were pains in the behind. I liked Philip but I wanted to know his story as much as Philippa did. We do find out in the end what it is.
This is a good story for 8-12 years old. The mystery is enough to keep one engaged and rooting for Philippa.