Tisala is a great blue whale, determined to save the last of his kind from being hunted to extinction. In an attempt to do this, he sets out on an expedition to understand why humans hunt. On the coast of the Scottish isles, he meets David, a young research biologist. David attempts to explain the misery and destruction of industrial whaling to Tisala, but, eventually, its Tisala who teaches David, offering new perspectives on philosophy, religion, ethics and the great issues facing humanity.