The Spanish Prisoner (1997)   David Mamet
http://www.imdb.com/title/tt0120176/

The Spanish Prisoner is a nice little Mamet character study that could  very well have been a play. Mamet’s dialogue style is fun for this – a tale about who you can trust and who you can not. Fans of THE USUAL SUSPECTS and THE STING will love this movie. It’s also a nice little vehicle for Steve Martin to sink his teeth into as he sheads his “wild and crazy guy” image and trades it in for serious and mysterious. A fun mystery that works well within the framework of what it tries to do.