This is one of the stranger movies I've seen in a long time. I had the same feeling after this that I did after Napoleon Dynamite, "What the hell just happened." While this one has its funny moments it's not another Napoleon.
It's about a retired German salt miner who plays accordion - yes, he's into polka. But one night he comes across zydeco music on the radio and becomes fascinated with it. Some hilarity and much oddness (including the 300 pound Schultze in a speedo in a hottub) later and you're left wondering what kind of mind came up with this.