This book is part of the Morgan the Unicorn collection in the Serendipity series. Morgan's friend, The Princess, is always busy working, setting the clocks in her castle. She learns that play is just as important as work when her unicorn friend disappears and she must search for Morgan.
The pictures in this book are very evocative for a children's book... I remember feeling very sad for the princess, who is lost as she looks for her unicorn friend. Not sure if this story teaches much of a lesson to most children, who naturally want to play instead of work, but it is a good illustration of why spending time with friends is important.