Emma loves going to Summerhill Stables for her riding lessons. One day she arrives to find that everyone is really worried. Tiggy, the stable cat, has disappeared. Emma hurts her ankle during her lesson and goes to sit down in the barn until she feels better. There she hears a strange squeaking noise and discovers that Tiggy has had three kittens! But the riding school can't look after so many cats - what will happen to them all?