With its rambunctious spirit, running jokes about ketamine, and a prominently displayed pair of pallid buttocks daubed with bluntly anti-British sentiment, the fictionalised origin story of real-life Irish-language rap group Kneecap (who play themselves) probably won’t be for everyone. But the combination of the profane and the political, the riotous humour and punchy editing makes for one of the more energising viewing experiences of the year, and possibly one of the funniest.