Imagine being unable to recognise your spouse, your children, or even yourself when you look in the mirror, despite having good eyesight and being able to read well and name objects. This is a condition which, in rare cases, some brain injury survivors experience every day. Identity Unknown gives an exceptional, poignant and in-depth understanding of what it is like to live with the severe after-effects of brain damage caused by a viral infection of the brain. It tells the story of Claire, a nurse, wife, and mother of four, who having survived encephalitis, was left with an inability to recognise faces – a condition also known as prosopagnosia together with a loss of knowledge of people and more general loss of semantic memory Part One describes our current knowledge of encephalitis, of perception and memory, and the theoretical aspects of prosopagnosia and semantic memory. Part Two, told in Claire’s own words, is an account of her life before her illness, her memories of the early days in hospital, an account of the treatment she received at the Oliver Zangwill Centre, and her description of the long-term consequences of encephalitis. Claire’s profound insights, clear writing style, and powerful portrayal of her feelings provide us with a moving insider’s view of her condition. These chapters also contain additional commentary from Barbara Wilson, providing further detail about the condition, treatment possibilities, potential outcomes, and follow-up options. Identity Unknown provides a unique personal insight into a condition which many of us have, for too long, known too little about. It will be of great interest to a broad audience including professionals working in rehabilitation settings, and all those who have sustained a brain injury, their families and carers.