Three women, carefully selected from public applicants, undergo special training designed to prepare them for rescuing others even in life-threatening water emergencies. The training is conducted like real combat: the coach forcibly submerges them, grabs their legs to prevent swimming, and subjects them to intense physical and psychological hardship. Enduring extreme suffering, some lose consciousness but are dragged to the poolside, where they continue to be tormented by the coach until the training finally ends. What impact will the terror, pain, and coercion they experienced leave on their minds?