Knife in the Water - Watch Your Back**I wrote about this song six years ago but was reminded of how much I loved it when someone randomly mentioned the Roman Polanski film that the band is (presumably) named after.**This song is unhealthy love. Wan and vengeful. The two characters in "Watch Your Back" live in an inscrutable world of smoke, humid nights, quick meals, minimal furniture, and crumbling walls. Malfunctioning cars that go only from home to work and back again. This song is the slow, unairconditioned, and gorgeously told disintegration of a relationship. Knife in the Water tell this kind of story well.The guitar in the beginning of this song is all-business, grinding out casual distrust, giving way to Aaron Blount's and Laura Krause's voices, which come together like dirty hands folded in prayer. Aaron and Laura harmonize in the same way that Low's Alan and Mimi do, but in this song their voices combine to make something that is dangerous, fraught with tension, and vigorously unnerving. Listen to the martial beat, the jaw-droppingly pretty pedal steel swells, and the guitar that sounds like it's chipping away at something, methodically. I would be hard-pressed to find a song that features such an intense and beautiful ending as "Watch Your Back": "Your heart beats out/your blood/a little slower now/than when/you turned/on me/I saw it coming down," scaffolded warily by Bill McCullough's pedal steel, Aaron and Laura's voices build and build, strengthened in their resolve by a spectating organ. If the band had stretched this song out to the 10-minute mark, it would have been perfect. It is pretty much perfect.[Buy Red River]