Blow chronicles the story of George Jung (Johnny Depp), a drug dealer whose ambition far exceeded his talent.
In the film, George starts with the dream of selling marijuana in small amounts moving on to large quantities, and finally graduating to cocaine. He moves, shakes, wheels, and deals until he is rolling in money, but is unaware that he is surrounded by friends who would betray him, and the authorities who want him put away behind bars.
The acting is excellent. While Depp and Penelope Cruz (who plays his wife) don't have that much chemistry on the screen, they do present a realistic portrayal of the ups and downs of power-based relationship where security is only an illusion and can be snatched away in an instant when a drug deal goes bad.
The movie's message could simplistically be that "crime doesn't pay". However, considering that I think that doing drugs routinely is generally an incredibly stupid activity, I think penalising such activity is just as inane, if not more so. In my view, if people wish to snort themselves till they can't feel their faces, it's their prerogative.
What the movie does illustrate is that one's life is essentially based on chance: "sometimes you're the windshield, and sometimes you're the bug." The thing to do is to take advantage of both situations instead of looking down at one. When George is down on his luck, instead of making good with what he has, he goes back to what has worked before, which proves to be recipe for disaster.
Blow is an interesting film and worth watching, and it suddenly seems that along with Chocolat, Depp is once again acting in movies worth watching. I recommend checking it out.