Earth has been taken over by a benign group of aliens known as the Monitors, gentlemanly figures clad in black overcoats and bowler hats. They are dedicated to suppressing humanity's propensities for violence, sex, war, and trouble, enforcing their ethos with spray cans of a pacifying gas and with television ads praising the Monitors' rule—the latter featuring cameos by a variety of comedic actors, as well as bandleader Xavier Cugat and Illinois senator Everett Dirksen (who died before the film's release).