This article examines the dynamics of collective behavior in Santiago, Chile every September 11, the date of the 1973 coup that brought General Augusto Pinochet to power. It uses a multiple-method strategy that includes participant observation, personal interviews, and content analysis of three major newspapers during the period 2003–8. The theoretical approach emphasizes time and space coordinates of specified social actors, sociocultural emergence, a limited range of dominant emotions, and dramaturgy to describe the complexity of ritualized commemorations. It shows that incidents occurring on this date are not primarily caused by the actions of social movement organizations. Moreover, the dichotomy of “day and night” used to understand the peaceful and violent commemorations is an oversimplification of a complex network of events, actors, and scenarios that has the effect of denying any legitimacy to actions that fall outside the state-approved practices.