Mike, working with a pretty Secret Service agent, poses as a scientist in order to retrieve a cache of counterfeit currency from a crashed Nazi plane off the coast of a Caribbean republic.

Mike faces arrows and an alligator in the Mayan jungle while searching for a drug that could be a boon to medicine or a dangerous narcotic.

Mike trains a pair of frogmen for a rescue mission in which they will rescue their kidnapped president from an ancient fortress.

One salvage diver disappears while diving on a sunken yacht off the coast of Yucatan, and Mike tries to see that two others don't share his fate.

Mike helps the daughter of his old UDT Commander investigate the man's death, which she believes was murder.