F for Fake, a 1973 docudrama directed by Orson Welles, Oja Kodar, François Reichenbach, Gary Graver within which actor Welles (Citizen Kane (1941)) investigates the lives of infamous fakers Elmyr de Hory and Clifford Irving.
Elmyr de Hory was a Hungarian-born painter and art forger, who is said to have sold over a thousand forgeries to reputable art galleries all over the world. He is possibly the most famous dodgy art dealer of all time.
Clifford Irving (1930 - 2017), was an American Novelist who is responsible for one of the biggest literary hoaxes of the 20th century. In the 1970's he wrote an autobiography billionaire Howard Hughes. All of the information contained in it was bogus despite claiming it was all based on interviews and meetings with Hughes. Sadly he passed away in 2017 (man 2017 was a bad year).