I'm not a big fan of chanbara (samurai films), which is somewhat required to get the most out of Kill!. It isn't entirely straight-faced and toys with genre conventions, but that's difficult to appreciate when you don't care much for the genre. Okamoto based Kill! on the same material as Kurosawa's Sanjuro, a film I've seen but hardly remember anything about.
A ronin arrives in a barren town, hoping to find a bit of work. The town looks deserted, not too long ago an uprising took place there, so the ronin appears to be dead out of luck. Desperate for food, he gets caught in a local feud that goes way above his head, but his will to survive is strong.
Kill! is just a smidgen over-the-top, which doesn't read as very funny when you're not too versed in rules of the genre. I mostly saw a very familiar setup with the usual elements I dislike about chanbara cinema. Crude characters, uninteresting drama and poor action scenes. Maybe I'll revisit it once I've seen more core genre efforts, but for now this was a big disappointment.