Leave this very minute and rent it. Take the rest of the day off!
I saw it in Korea years ago. It came out the same time as Res Dogs and some of those other "gangster" movies, so it didn't do well in the states. When it was released on DVD it was one of those cult hits.
It still ranks as one of my all time favorites. The Willam Defoe part is a little over the top in places, but there are some subtle parts that just rock. Some dialog that you'll miss the first time because of the accents.
Connor: Okay, Roc...
[Connor looks at him and laughs; his mask is badly put on]
Rocco: What? You guys got masks.
Murphy: You look like Mush Mouth from Fat Albert.
[as they keep giggling, Rocco takes his mask off]
Rocco: Fine! *bleep* it. When we're done, she can ID me. I don't care. Just trying to be professional, but nooooo...
Connor: It looks fine!
Rocco: *bleep* it.
Connor: Now shut the *bleep* up, you look good. Put it on! You look fuckin' scary, man!
[Rocco puts his mask on, again badly]
Connor: [trying not to laugh] Now Roc, are you sure that you're obee-kay-bee?
Connor: Jeez! It's a fuckin' six-shooter. *bleep*!
Murphy: There's nine bodies, genius.
Connor: What the *bleep* were you gonna do, laugh the last three to death, Funny-Man?