Puccini began work on Turandot in 1920 and had completed all but the final duet between Calaf and the princess when he left for Brussels early in November 1924 for radium treatments for throat cancer. Though he brought his sketches for the final scene with him, he died of cardiac arrest on the 29th, leaving the work unfinished. Using Puccini's sketches, composer Franco Alfano devised an ending in time for the premiere. Toscanini, however, who was conducting, put down his baton where Puccini's music ended, saying, "Here the opera ends because at this point the Maestro died."