"Infernal" is a high-energy brush-swing/"Montuno" Latin hybrid that pays homage to several esteemed composers of the Big Band tradition (originally written as a contrast to "Violet", another chart of mine). The ten-minute journey brings the band to varying macro-formal textures, guides them to experience of large shifts of velocity, and certainly brings them to an outer limit of the human viscera and nervous-system that can exist in large ensemble swing. It's a breaker for the chops, but it's a good opener or closer.