Mandatory Credit: Photo by Guy Bell/REX/Shutterstock (5689443ab) The Mayor of London Sadiq Khan is interviewd after watching Londoners as they warmed-up at City Hall for the international Big Dance Pledge. Big Dance Pledge, City Hall, London, Britain - 19 May 2016 On Friday 20 May, over 40,000 people in 43 countries around the world will take part in the Big Dance event, which has been specially choreographed by Akram Khan. Among the Londoners were: Students from University of Roehampton; MovE17 community group; Children from John Scurr Primary School; and the Croydon Community Dance group. This year is the finale of Big Dance, celebrating ten years of grassroots and community dance.