Employee creativity is critical to organizational competitiveness. However, the potential contribution made by the workspace and the physical environment is not fully taken into account because, up to now, it has been rather unclear how aspects of the physical environment, especially light, can support creativity. Consequently, in six studies, the present research investigated the effect of light and darkness on creative performance. We expected that darkness would offer individuals freedom from constraints, enabling a global and explorative processing style, which in turn facilitates creativity. First, four studies demonstrated that both priming darkness and actual dim illumination improved creative performance. The priming studies revealed that the effect can occur outside of people's awareness and independent of differences in visibility. Second, two additional studies tested the underlying mechanism and showed that darkness elicits a feeling of being free from constraints and triggers a risky, explorative processing style. As expected, perceived freedom from constraints mediated the effect of dim illumination on creativity. Third, moderation analyses demonstrated the effects' boundary conditions: the darkness-related increase in creativity disappeared when using a more informal indirect light instead of direct light or when evaluating ideas instead of generating creative ideas. In sum, these results contribute to the understanding of visual atmospheres (i.e. visual messages), their importance for lighting effects, and their impact via conceptual links and attentional tuning. Limitations as well as practical implications for lighting design are discussed.