Hi everyone!

Since a few months ago I keep op thinking about this film I've watched a long time ago, but can't seem to find. I've tried going through the plot synopsis of many a film about scammers and conmen, but my effort hasn't been fruitful...

This is what I remember of the plot:

The film I'm looking for starts with the main character, a con artist, telling his life story to a journalist or writer of some sort, in a park. He's promised to sell the manuscript of his life story to the journalist. He tells him a con artist gives his victims what they most desire, they believe in his lies and ignore any inconsistency because they want it to be true so badly.  One of the major parts of his life story involves the elaborate story of how he convinced an Italian Mafioso that he was making a Hollywood film for his son. Complete with a chasing scene with speed boats or cars or whatnot. After the con artist is done with his story and the journalist is completely in awe, he buys the manuscript but after the man leaves he finds out the manuscript is just a bunch of blank papers. We then question ourselves whether the con artist made these stories all up as well, because we and the journalist wanted to believe in his crazy story so badly.

I don't think I came up with this elaborate plot in my sleep. This film must exist somewhere! Please help me find it!