 The S. S. Claridon is scheduled for her five last voyages after thirty-eight years of service. After an explosion in the boiler room, Captain Robert Adams (George Sanders) is reluctant to evacuate the steamship. While the crew fights to hold a bulkhead between the flooded boiler room and the engine room and avoid the sinking of the vessel, the passenger Cliff Henderson (Robert Stack) struggles against time trying to save his beloved wife Laurie Henderson (Dorothy Malone), who is trapped under a steel beam in her cabin, with the support of the crewmember Hank Lawson (Woody Strode).