This study conceptualizes and empirically validates the “Tactical Long-tail”—a hybrid strategic phenomenon integrating traditional blockbuster and long-tail frameworks—to explain structural shifts in the Korean film market following the COVID-19 pandemic. Utilizing data from the Korea Box Office Information System (KOBIS) spanning 2017 to 2023, the analysis employs the Herfindahl-Hirschman Index (HHI), the Concentration Ratio (CR), and the Gini coefficient to measure market dynamics. The findings reveal that at the macro-level, market concentration among the top ten films nearly doubled in the post-pandemic era, reinforcing the industry’s blockbuster-centric nature. Paradoxically, a micro-level shift occurred within this leading tier: rather than being dominated by a static few, the top rankings exhibited accelerated turnover and increased diversity, characterized by multiple high-performing films cycling through peak positions over condensed durations. This pattern indicates that distributors and exhibitors have adopted risk-diversification tactics to mitigate demand uncertainty and facilitate streamlined transitions to OTT platforms. By demonstrating how long-tail principles can be tactically operationalized within the physical constraints of theatrical exhibition, this research provides critical insights into evolving film distribution strategies in the post-pandemic landscape.