As the tour began, everyone was in good spirits, but the later shows were marred by Roger Waters' increasing annoyance with the raucous fans in attendance. During the last show in Montreal, a noisy fan near the stage irritated Waters to such an extent that he spat on him. The act so disgusted David Gilmour that he left the stage prior to the final encore, ""More Blues"", leaving Snowy White to fill in as the roadies began dismantling the stage equipment. The insatiable audience clamored for the band to keep playing, and a small riot broke out in front of the stage following the band's eventual exit. Later that night, Waters recounted the incident to his friend, music producer Bob Ezrin, and expressed his growing feelings of alienation toward their fans. Those feeling of detachment became the starting and focal point for Pink Floyd's next album, "The Wall".