Young and green Jack Wright is determined to prove his late father was not a madman and his submarine invention not folly. Down to his last dollar Jack and his new recruits sailor Timothy Topstay and the Dutch-German electrician Fritz Schneider with much fanfare launch the remarkable Sea Spider. Unfamiliar with deep-sea travel, after wrecking it on its maiden voyage and recovering the sunken boat the unlikely trio finally set out to find the sunken Spanish treasure his father sought. But will Jack's inventions be enough to save them from pirates, sharks, head-hunters, slave traders and a...