F for Fake was Welles’ attempt to establish a new cinematic form: that of the film essay. Its ostensible subject is a documentary by François Reichenbach about a great art forger, Elmyr de Hory, who is interviewed by Clifford Irving. The irony is that this master forger is being interviewed by a man who will be exposed as an even greater fraud than his subject (Irving being the fake biographer of Howard Hughes). Armed with this hindsight, Welles begins to play with the material, manipulating Reichenbach’s documentary so that its veracity — indeed the veracity of documentary itself — begins to come under question.

The very nature of art, Welles reminds us, is a mystery analogous to magic. He quotes Picasso: ‘Art is a lie that makes us recognise the truth.’ Welles’ own films always come at truth not through a surface, or surfeit, of realism, but through an imaginative expressionism or distortion. He gives a definitive demonstration of that in this film’s finale, where he ‘lies his head off’ yet animates photography into life with such art that disbelief is suspended.