Renowned filmmaker Fernando Meirelles, best known for the intense 2002 film about the Rio slums “City of God,” leads an all-star cast of artistic directors that also includes Andrucha Waddington, Rosa Magalhaes, and Daniela Thomas with choreographer Deborah Colker managing 6,000 volunteers to dance in front of an expected capacity crowd of 78,000 and the millions watching at home. “I am bringing a lot from the studies that I had been carrying out,” Colker, who’s been running rehearsals since May, told the official site.