While a menacing typhoon approaches, an accident at the giant natural gas plant Regalia occurs. Japan Coast Guard rescue divers Daisuke Senzaki (Hideaki Ito), Tetsuya Yoshioka (Ryuta Sato) and engineer Hiroshiichirou Sakuragi (Masaya Kato) head together to the gas plant. During their rescue efforts an explosion occurs that traps Daisuke, Natsu Nishizawa Kazue Fukiishi...