This is a picture book about the invention of insulin. It’s very well done and it’s an interesting story. The illustrations work quite well, and they make this big topic approachable to children of many ages. Reading this book has the side effect of making me mad. The book does say that Frederick Banning, the person who discovered insulin, sold the rights to it for one dollar because it belonged to the world, not to one person. Yet our drug manufacturers sell it for way over what it costs to produce, and they did not have a hand in inventing it. This book is a reminder that medicine in the US is a horrible game of cat and mouse that far too many people die from.