A continuation of the story of Timothy the field mouse. In this book the adventures of Timothy and his sister Timothina continue as they adapt to the life by the their farm pond. The watery world of the pond with its creatures, mystery, and lessons to learn are the subject matter of this book. This is a tale of change, contrasts and transitions. Creatures who live in the water are contrasted with dry land creatures. Creatures who are dependent on the pond are described. Probably most importantly creatures that are wild and free are contrasted with those that are not, and everything about the life of the pond mouse is in a constant state of transition and change.