Crack in the World

Leader of the project, secretly dying of cancer, believes the atomic device will burn through the barrier to reach the core. He remains at the underground control center to monitor and record the events, facing both scientific and personal pressures. His resolve drives the action and moral gravity of the narrative.

Chief geologist who argues the lower crust has been weakened by decades of underground tests and that detonation could trigger a world-changing crack. He is cautious, analytical, and ultimately proven right about the dangers. His warnings create the central tension between risk and knowledge.

A senior project administrator representing international interests, trying to balance scientific ambition with political and global repercussions. He mediates between scientists, diplomats, and leaders as the crisis unfolds. His role emphasizes the cross-border stakes of the endeavor.

Sorenson's wife, part of the high-pressure environment and emotionally invested in the fate of the team. She pleads for caution and evacuation, highlighting the human cost of the crisis. Her perspective adds a personal dimension to the scientific pursuit.

A project staff member involved in operational aspects of the mission, contributing to the coordination and execution of the dangerous experiment. He represents the bureaucratic and practical side of the operation.

Senior scientist aiding the team, providing expertise and participating in the decision-making process under extreme pressure. His involvement underscores the collaborative nature of the project.

A technical staff member whose routine tasks contribute to the tense atmosphere of the operation. He represents the many behind-the-scenes workers in a high-stakes scenario.

A project staff member whose presence adds to the human dimension of the crisis. She participates in the escalation of the tension as events unfold.

Diplomatic liaison representing global governance in the crisis, illustrating the international political stakes of the project.

A supporting member of the project staff; the film does not detail his specific duties, but his presence contributes to the tense operational atmosphere.