Moving in harmony can make people feel more connected to one another and, as a result, lead to positive collective action. Think of those feel-good vibes created in a yoga class as students move in unison through their downward-facing dogs. Yet given that synchronized physical activities are also a cornerstone of military training and are the highlights of military propaganda reels, could the interconnectedness created by coordinated action be mined to make people behave destructively instead? Two new studies find aligned action does not always lead to the common good.