The crew of a five-man submarine travels the world oceans, planting sensors on the ocean floor to warn scientists of any impending earthquakes.

Follows the adventures of a crew of the deep-diving nuclear-powered civilian research submarine Hydronaut making a submerged circumnavigation of the world to plant monitoring sensors on the ocean floor that will help scientists better predict impending earthquakes.

Due to the increased frequency and severity of seismic activity beneath the world's oceans and increased potential of catastrophe especially to coastal metropolises, marine scientists Dr. Doug Standish and Dr. Craig Mosby, developers of the deep sea vessel, The Hydronaut, are assigned the leads, by the Federal Science Council under the approval of the US government via the Vice President, of a dangerous three to four month mission to install fifty sensors on the ocean floors throughout the world as the mechanisms of an early warning system of said seismic activity. Free to choose their small crew, "small" necessary due to the what can be accommodated aboard the Hydronaut, Standish and Mosby have as difficult a time to recruit who they want - and in one case who they don't want - as the actual mission itself. That crew ends up being: geologist Dr. Orin Hillyard, and biologist Dr. M.E. Hanford, who is also to act as medic, with the support team of communications and electronics expert Dr. Phil Volker, and Hank Stahl, a self-taught Renaissance man and recluse who is to act as mechanical engineer. The dangers of the deep sea aspects of the mission are well known in very little globally being understood about the geographic areas in which they will be working. What ends up also being problematic are the interactions between and motivations of the six disparate members. The three most problematic areas are: certain scientists wanting to pursue their own scientific endeavors which may impede on the core mission; conflicts between Dr. Volker and his technology perspective and Stahl and his human ingenuity perspective; and Dr. Mosby's concern about the one he didn't want, Dr. Hanford, "Maggie", the only female aboard. While initially unaware of Dr. Hillyard being her current boyfriend and Dr. Volker being her former boyfriend who still has feelings for her, Dr. Mosby was worried about his own attraction to her and that attraction being a distraction to their work.—Huggo