And it's surprisingly innocent.
There's no ratcatcher here, and no children being snatched from their parents. Quite the opposite. As Frank Cottrell Boyce points out: Chitty Chitty Bang Bang is "one of the very few stories in which the whole family goes off on the adventure – usually children have to be sent away to school or evacuated or bereaved or fall through a time vortex before an adventure can start."
So Chitty Chitty Bang Bang really is a book for all the family. And if you want more, Frank Cottrell Boyce has now written three sequels.
If you want a sample, you can read the first chapter of Chitty Chitty Bang Bang Flies Again here.