This article examines the unfolding joy in young children's literacy practices in a Finnish early years classroom. We focus on the unfolding of joy in intra-action among children, adults and materials during literacy learning endeavours by thinking with "new" materialist theories, and the data from an early years multiliteracies project named The Storybook. Our goal is to draw attention to the material and relational dimensions of young children's joy in its moment-to-moment unfoldings by examining how joy unfolds unexpectedly in a moment when children, adults, Storybooks and other material resources intra-act.