The Deuce: Dangerous Waters - Matt Ritter, #2

When Matt Ritter and the crew of the dive boat The Deuce respond to an SOS from a research vessel being attacked and sunk, they end up rescuing billionaire Phillip Gibson and his crew. Gibson is in possession of the diary of a Spanish Galleon that disappeared during a hurricane with nearly two billion dollars worth of gold. To repay his gratitude, Gibson hires part of the crew to help him recover the diary from his sunken ship, then continue his search.
But, Dominic Kelso, part of an international smuggling cabal, has his eyes on the treasure, and kidnaps Gibson and four members of The Deuces' crew and force them to continue the search after destroying their ship and faking their deaths during a storm, Expecting no help from the Coast Guard, and with no clue as to their wherabouts, Deuce crew member and Army veteran Pamela Griggs leads a team on a mission to locate and rescue them.