I don't think it matters if you liked, hated, or haven't even seen BOONDOCK SAINTS to enjoy OVERNIGHT. It's simply a great view into the mind of a guy who feels he is automatically supposed to be the next Tarantino before ever yelling "action." But if you did hate SAINTS you will probably have a good time seeing this guy's rise to fame explode in his face.
I actually liked SAINTS as a mindless vigilante flick, but after seeing OVERNIGHT I can't figure out how the guy was able to put it together. One of the doc's few faults is a lack of footage of SAINTS being shot. I have no clue how a guy who never went to film school and doesn't appear to have a real passion for film made anything that looks like a motion picture with $7.5 million.
The funniest parts of OVERNIGHT, aside from Duffy talking to a class of film students, are early on when Duffy starts ripping on actors who might play the leads in SAINTS. He vows he'll never do a movie with Keanu Reeves and calls Kenneth Brannagh a cunt. Of course the film's leads ended up being Sean Patrick Flanery and Norman Reedus.