Traditional Islamic boarding schools in Indonesia are commonly shaped by charismatic, genealogical, and kyai-centered authority, making leadership succession a critical yet psychologically complex process. While previous studies have largely examined succession in terms of institutional continuity, leadership style, or authority transfer, limited attention has been given to sudden succession as a lived psychological role-transition process. This study explores how sudden leadership transition is experienced by a young successor and interpreted by members of a traditional Islamic boarding school community in West Java, Indonesia. Employing an instrumental qualitative case study design, data were collected through semi-structured interviews with three purposively selected participants: the young successor as the primary participant, a pesantren staff member, and a senior student. Data were analyzed using theory-informed thematic analysis guided by Nicholson’s Transition Cycle. The findings reveal that sudden succession unfolded through overlapping phases of forced role entry, emotional disruption, relational ambiguity, adaptive coping, and partial stabilization. Rather than reflecting a smooth transfer of authority, the transition involved psychological adaptation by the successor, relational negotiation with the community, and religious meaning-making that transformed unwanted responsibility into moral obligation. This study contributes conceptually by extending Nicholson’s model to a collectivistic and religious educational context, demonstrating that leadership transition in traditional Islamic boarding schools is not only an individual role-adjustment process but also a communal and spiritually mediated reconstruction of authority. The findings highlight the need for psychologically sensitive succession preparation, mentoring, and community-based support in traditional Islamic educational institutions.