Even given this decade’s ever-accelerating blurring of genres, Babymetal’s signature sound is a bewildering proposition. Their mix of speed metal’s whipsmart riffs and pummelling rhythms with dance dynamics topped with J-pop vocals, courtesy of teenage girls Su-metal, Yuimetal and Moametal, is not one for the purists (the existence of a shadowy svengali figure, Kobametal, doesn’t help on that score). And yet this high-speed collision of apparent opposites works surprisingly well. Their second album is a relentless blur of ideas and rule-breaking, with GJ! and Sis. Anger particularly strong. Wisely, they save their only two missteps for the end: power-ballad No Rain, No Rainbow is wearyingly formulaic, while the one foray into English lyrics on The One unpicks some of their exoticism with its platitudinous observations.