under the command of captain lee crane and with admiral harriman nelson, vice-admiral b. j. crawford, congressman llewellyn parker, and psychologist susan hiller aboard, the nuclear-powered submarine usos. "seaview" goes under the arctic ice for a shakedown cruise. partway through the cruise the crew find that the ice is melting and when seaview surfaces they see that the sky appears to be on fire. radio communication is extremely difficult, but they get a request to come to new york, where the un is holding a meeting of top scientists. after rescuing a man, alvarez, from an ice floe, they head south.