国际知名合唱团铁血指挥家严梓朗（刘德华饰），为帮助昔日恩师（卢冠廷饰）返回香港，带领一群因闯祸而被迫参加“热血合唱团试验计划”的废柴学生们，从零起步学习合唱。众人共同面对生活的挫折与挑战，最终在音乐中找回了自我，而严梓朗身上的秘密也逐步被揭开……Yan Zilang is an internationally acclaimed conductor working in the United States. After his former teacher inherits a group of problem students, Zilang returns to Hong Kong to assist with training them. Although it won't be an easy task, Zilang is prepared to do everything he can to help the kids find their voices.