The Dutch Twins are Kit and Kat, 5 years old and not yet big enough to be called by their real names, Christopher and Katrina. They live in a typical Dutch household, around the turn of the last century. The book follows their day-to-day adventures and accidental mishaps. The book is the first of a series of stories about twins in different countries, meant to give children an idea of life and customs in various parts of the world.