A holistic thinking style shaped by culture is associated with emphasizing the whole picture, utilizing more informational content in reasoning, accepting contradictions, and being flexible in dealing with change. Its holistic interconnectedness subdimension involves focusing on the relationships between objects and context (Choi et al., 2007). Increasing holistic thinking can be effective in addressing modern world problems such as the climate crisis and economic inequality. In this study, we developed a new video to enhance holistic interconnectedness. The video showed connections between objects and systems. In the control group, we used a similar video without content on connectedness. After watching the video, the participants (N = 559) completed the causality and locus of attention subscales of the Analysis-Holism Scale (Aytürk et al., 2024; Choi et al., 2007) and the Inclusion Task (Choi et al., 2003). We implemented a group sequential design with two interim analyses (Lakens, 2014). According to the independent groups t-test results applied in the first interim analysis, the video activating holistic interconnectedness significantly increased the understanding of causality (t(527.2) = 2.56, p = .01). However, it did not significantly change scores in the locus of attention and inclusion task. The effect size for the locus of attention was too low to continue; however, the study could continue with the inclusion task scores. Nevertheless, we stopped data collection due to research resource considerations. We suggest using video as a new method to activate holistic interconnectedness in future research, enabling the study of its effects on psychological processes. We also recommend group sequential designs as an efficient method for developing interventions, enabling effectiveness to be tested earlier during data collection without inflating error rates. This research was supported by the Scientific and Technological Research Council of Türkiye (TÜBİTAK) [Project Number: 221K040].