This book is based on the real life of Etzel von Oeringen, known as Strongheart, whose hugely popular movies introduced Americans to the German shepherd. The breed, developed in Germany at the end of the nineteenth century, was highly intelligent, brave, and loyal, and was adoped by the German army and police. Larry Trimble, a pioneer movie director and animal trainer, was auditioning dogs to star in a movie when he first encountered Etzel in a...