When the Van Allen radiation belt suddenly catches fire and threatens to destroy all life on Earth, the nuclear-powered super-submarine Seaview embarks on a dangerous mission to extinguish the flames and save mankind from extinction. Travelling undersea, the brave crew must survive oceanic horrors and stop a saboteur in their midst before they can help avert certain doom. Walter Pidgeon, Joan Fontaine, Barbara Eden, and Frankie Avalon star in Irwin Allen's sci-fi epic. 106 min. Widescreen; Soundtracks: English DTS HD Surround Master Audio, Spanish Dolby Digital stereo, French Dolby Digital mono; Subtitles: English (SDH), Spanish; audio commentary; documentary; interview; isolated music score; theatrical trailer.