Paul Turner (John Bentley), a military tactician with little seafaring experience, is assigned as lieutenant commander on the USS Seahawk. Turner is to pilot the submarine on a secret mission, about which his crew is kept in the dark. Inevitably, they resent their new leader for his privileged information, adherence to the rules and refusal to fire on the Japanese subs that they spot. Eventually, they learn Turner is just following orders, and the Seahawk is on a veritable suicide mission.