In terms of stepping stones, and books that change the world, the book written by Patrick Murray is of such an ilk. That in the subject it brings to light; a harrowing account of reality behind what so long has been thought to be exclusively a medical condition. The extraordinary story in the context and detail it occurred, is a revelation for humankind. It is not only a testament to the unseen world, that it exists, but that we coexist with life forms we cannot see, but never the less, some of which are able to influence us, and in a very negative way, and do us harm. For those interested in the supernatural, mind body and spirit, or something unusual and unique, The Unwanted Companion is a must read. But of further importance is that it is a book that should be mandatory reading for all training and qualified psychiatrists, the world over, and all those working in these fields.