When teacher leaves the classroom, three naughty Chinese schoolboys in detention abandon their lines – “Be a Good Student!” – to burst into mock-rock and wild oriental gestures. When a pretty female classmate joins them, they boisterously compete for her attention with gymnastic flings and pretend serenading, but she prefers to dance in traditional flowing robe – and then join them for musical mayhem on bins, shakers and coat-hangers.

Their fiercely strict teacher returns to vent her rage, but a romantic phone call suddenly releases her alter egos as exotic belly-dancer and daring trapeze artist. Lisa Cheng’s exploit in swinging from a high-up fan unit is both a dramatic surprise and acrobatic tour de force.

Mayhem upon mayhem ensues as the teacher vainly tries to control her wayward pupils, ever ingenious as they outwit her with frenzied movement, teen clowning, non-verbal cacophony and cleverly improvised music bursts.

Liu Hong-wah as the sweetly strong girl, and Zico Hau, Franky McNugget and Aska Leung as the high-octane lads, superbly sustain comic appeal – then stage a splendid finale on traditional Chinese drums.

Director Tang Shu-wing scores a Fringe triumph with his youthful Hong Kong company in this very inventive and highly amusing show.