Tracy and Matt, Michelle and Sebastian: these are the two couples whose lives of addiction, crime, and squalor are brilliantly captured in this raw and honest HBO documentary. They're in turns petulant, charming, repulsive, astonishingly stupid, and dedicated: to the drugs and to each other. They're also each very different: Matt is a working class boy who clearly revels in his naughtiness, whilst prep school dropout Tracy supports the couple with Western Union money from her moneybags father, who makes a surprisingly sympathetic cameo towards the end of the film. Meanwhile widow Michelle (whose hubby died of an OD) earns her daily bread by posing as an NYPD vice cop willing to cut her would-be Johns a deal to avoid prison time, and sad sack companion Sebastian lives off the proceeds. You'll be pulled into their stories and will wish the film went on for twice as long. Unlike most documentaries of this kind, there's no coda providing us with an update about their progress (can Matt and Tracy really keep that Brooklyn apartment? Will Michelle go back to Bellevue for more detox? And can Sebastian become any more pathetic?). As a result, the film seems incomplete, but that may have been the point. Essential viewing, as long as you aren't completely averse to scenes of people shooting up.