The Fregoli delusion is one of a number of misidentification syndromes. It is characterised by a patient recognising a familiar person, usually seen as a persecutor, in various strangers who, although they do not show physical resemblance, are believed to be psychologically identical to the familiar person. It usually occurs in the context of a schizophrenic illness but has been reported in affective disorders and organic psycho-syndromes (Förstl et al, 1991). It was first described by the French authors Courbon & Fail in 1927, who used the term ‘Fregoli illusion’ after the Italian actor who enjoyed enormous popular success on the Paris stage at the time. It has also been called the ‘illusion of negative doubles'. However, as the psychopathology is a delusional interpretation of normal visual stimuli rather than an abnormal perception the terms Fregoli delusion or ‘delusional hyper-identification of the Fregoli type’ are preferable. The original case description has recently been translated and annotated (Ellis et al 1994) but there remains little background information available on the figure of Fregoli himself. Biographies have appeared in French and Italian but there are few English language references and this paper is intended to provide an account of the life and career of one of the most extraordinary entertainers in theatre history.