This article advances theory on social movements’ strategic adaptation to political opportunity structures by incorporating a narrative perspective. Our theory explains how people acquire and use knowledge about political opportunity structures through storytelling about the movement’s past, present, and imagined future. The discussion applies the theory in an ethnographic case study of the climate movement’s mobilization around the UN Climate Summit in Paris, 2015. This analysis demonstrates how a dominant narrative of defeat about the prior protest campaign in Copenhagen, 2009 (...) shaped the strategizing process. While those who experienced Copenhagen as a success preferred strategic continuity, those who experienced defeat developed a “Copenhagen narrative” to advance strategic adaptation by projecting previously experienced threats and opportunities onto the Paris campaign. Yet by relying on a retrospective narrative, movement actors tended to overlook emerging political opportunities. We demonstrate that narrative analysis is a useful tool for understanding the link between structure and agency in social movements and other actors affected by (political) opportunity structures. (shrink)