Love. Greed. Revenge. And a desperate search for answers ... Against the stunning backdrop of the Great Barrier Reef, two women in different eras discover how their hearts and fortunes are swayed by the secrets of the sea.

2019: Bethany Kristensen faces her toughest challenge to date, skippering the family charter business. With rivals doing their utmost to undercut her prices and reputation, the Kristensens' operation hangs by a thread. Winning the tender for a new scientific research program headed out to the farthest edge of the reef is her last chance to keep the business going. But when rumour and vandalism turn to outright sabotage, things take a drastic turn...

1934: Stella Booth flees a future of domestic drudgery in small-town outback Queensland, heading for employment and an independent life in Mackay. But fate has other plans and an accident en route sends her life spinning in a most unexpected direction...