Con artists work by gaining your confidence. Hell, it's in the name. Sometimes this is done by creating a thorough and plausible identity. Other times, they just wing it and hope no one will ask questions. Perhaps one the most ballsy types of this scam are people who claim to be close relatives of famous people, especially when those people do not exist. I recently heard about the case of Alison Reynolds, who in 2003 went around claiming to be TS Eliot's twin daughters, Claire and Chess, while scamming the British theater establishment for large sums of cash. There are two basic problems here: TS Eliot had no children, and Reynolds was incapable of being in two places at once. She was forced to drop the identity "after theatre staff became suspicious that they had never seen Claire and Chess in the same room." What's baffling is that she was able to get away with this in the age of Google. I'll be honest, I'd watch a movie about a con woman claiming to be the non-existent twins of a famous playwright and, if history is any indication, we might well get one.
A similar scam was perpetrated in Manhattan in the early 1980s, when David Hampton went around claiming to be Sidney Poitier's son. (Poitier has six daughters, but no sons). His story was the basis of the play and movie Six Degrees of Separation.
But of course, if we're talking about celebrity impostors, we have to acknowledge the infamous Alan Conway, who didn't settle for pretending to be related to Stanley Kubrick, but claimed that he was Stanley Kubrick. If you think it's a bit funny that a con artist would be named Conway, well so would he, considering that he chose the name for himself, after being charged with numerous frauds. But this is just the kind of boldness you'd expect from a guy who, despite being British, clean shaven, and having "had apparently only seen a couple of Kubrick's films," managed to keep convincing people he was the real deal. The story of his unmasking is worth a read. It was largely left up to the real Kubrick's assistant, Anthony Frewin, who later went on to write a screenplay about the ordeal, titled Colour Me Kubrick.