A grudge between two divers whom Mike is testing for underwater mining skills becomes a secondary issue when one of them contracts nitrogen narcosis.

Mike trains three brothers in the use of scuba gear, unaware that they plan to break a fourth sibling out of Alcatraz.

While supervising an expedition in the Indian Ocean to find a rare coelacanth fish, Mike finds that the organizer is dangerously eager to impress his fiance.

Scientists risk triggering a tidal wave when they ignore Mike's warnings about the strength of the explosive charges they're using.