Since its publication in the Brundtland Report, the sustainability discourse has largely occupied international debates. Within the scientific, political, and economic domains, scholars have studied this issue with uneven emphasis depending on the direction of other global affairs. Yet, although this topic is interdisciplinary per nature, the existing literature on sustainability is quite polarized. It is only recently that it has registered contributions from a broader pool of academic fields. In this scenario, the thesis argues that there are hybrid ways of doing research that can offer critical insights into sustainability. Therefore, the present work harbors arts, social semiotics, and multimodal investigations to help bridge the mentioned gap in the study of durable development. Ontologically framed by post constructivism and post-humanism, it is relevant to underline that the thesis’ concepts (for instance, the very notion of art) are not intended as objectively definable entities but rather as ongoing social practices. In this optic, the epistemological roots of the investigation consisted of interpretivism and hermeneutical phenomenology, and Actor-Network Theory was chosen as the overall iterative strategy. Considering these fundamental pillars, the present research identified Aqua Mater, an art exhibition for 2022 Word Water's Day, as its case study. In detail, after that a micro ethnography of practice has collected the data, starting from Salgado's photographs, the analysis has blended multimodality and semiotics. More specifically, to approach the dense dynamics of the signification of the exhibition, the research designed an analytical route that connected, among others, Lemke’s (1993) study of the three aspects of meaning-making (namely the Presentational, Orientational, and Organizational one), with Iedema’s (2003) understanding of resemiotization, and Van Leeuwen and Jewitt’s (2004) ‘Handbook of visual analysis’. In this respect, the first phase of investigation of photo 23 was followed by a second phase focused on picture 24 and, finally, a concluding one deeming the two photos together. As a result, the findings revealed that the actors of the photographic representations (i.e. light, water, etc.) interacted with each other, at times, to invite the viewers to react to specific messages and, at other times, to present powerful cultural symbols triggering critical thinking. Besides, from a semiotic perspective, the research has explored and described how meanings were not homogeneously negotiated, thus, made indisputable, but rather they remained open to change and were mediated by the overall dynamicity of the communicative space. In conclusion, the thesis argued that, although events like World Water’s Day create inspiring spaces for social and critical reflection, creative or art-based (re)actions to sustainability issues are yet to be socially agreed upon.