Hossal, a distinguished Zol Empire physician, devotes his existence to eradicating Black Wolf Fever, a lethal plague ravaging his homeland. The death of his mother to the disease fuels his relentless quest to unravel why Aquafaese individuals possess immunity while Zolians succumb. This scientific urgency compels him to pursue Van, a former Aquafa soldier whose survival after a wolf attack suggests vital antibodies.

Rejecting widespread notions of the plague as divine retribution, Hossal clashes with a military leader resigned to fatalism. He champions science as humanity’s tool to reshape fate, prioritizing healing over borders or ideology. His conviction draws him into an uneasy pact with Sae, an Aquafa huntress determined to eliminate Van to protect her people’s rebellion.

As their paths intertwine, Hossal confronts the tension between medical ambition and moral compromise. The trio’s reluctant collaboration pivots when they unite to rescue Yuna, Van’s adopted child, binding their destinies beyond initial rivalries.

While the source novel portrays Hossal’s crusade as parallel to Van’s, the film adaptation merges their journeys, spotlighting shared purpose. This shift underscores Hossal’s transition from isolated scholar to engaged ally, navigating political strife and fragile alliances without abandoning his cure-seeking resolve.

Visually, his pragmatic compassion manifests through keen observation and resolute bearing. The narrative centers on his role as healer and strategist within the trio, his maternal loss anchoring his drive, while interactions with allies and adversaries propel intertwined medical and political stakes.