The artist otherwise known as Sting deserved some kind of medal for the promotion of interdisciplinary understanding (the Crossover Cross?) when he arranged for the prima ballerina assoluta Alessandra Ferri to dance while he played a guitar transposition of the Prelude from Bach’s Cello Suite No 1 in G major, with choreography by Heinz Spoerli and understandably lingering direction by the dancer’s husband, Fabrizio Ferri. The actual duet takes about two and a half minutes to get started, but since Alessandra Ferri, throughout her career, was fascinating even when standing still, there is no danger of the viewer’s attention straying.