The tale commences as Yume, a girl in middle school, catches sight of an object descending from the sky and encounters a kitten with a hue of pale violet named Mew. It transpires that Mew is endowed with the extraordinary ability called "Yume Synchro," signifying Dream Synchro, which enables entry into people's dreams. In the realm of dreams, both Yume and Mew gather Dream Stones.