After completing "Low" and ""Heroes"", Bowie spent much of 1978 on the Isolar II world tour, bringing the music of the first two Berlin Trilogy albums to almost a million people during 70 concerts in 12 countries. By now he had broken his drug addiction; biographer David Buckley writes that Isolar II was "Bowie's first tour for five years in which he had probably not anaesthetised himself with copious quantities of cocaine before taking the stage. ... Without the oblivion that drugs had brought, he was now in a healthy enough mental condition to want to make friends." Recordings from the tour made up the live album "Stage", released the same year. Bowie also recorded narration for an adaptation of Sergei Prokofiev's classical composition "Peter and the Wolf", which was released as an album in May 1978.