An unprovoked assault occurs when a total stranger assaults a totally innocent victim he has never met. Presenting findings from three such cases, representative of a series of ten seen as part of his work as a psychoanalyst at a special forensic hospital in the UK, the author attempts to tie together the victim and his attacker in the attacker's mind, setting out to explain how the victim fits the need of a psychotic man's fantasy, at a particular time. A provisional hypothesis about the internal situation of such patients and its diagnosis, treatment and management is put forward and discussed, in the context of the implications for the treatment of such offenders and the psychoanalytic theory of projection and symbolisation.