新生High-Grade Joe模仿流行嘅便利店健身房,開咗間「Choco Grey」。將後生女仔逐個洗腦…。喺健身房呢個舞台上,進行前所未有咁Hard嘅High-Grade,阿黑阿黑!搖住對波,喪咁插入個閪!逐漸增加會員,High-Grade連鎖反應停唔到!用High-Grade賓周環,從個閪度射到勁水!