If Emme Clark can’t obtain proof of her husband’s death, she’ll lose everything. The bloody Commodore Cobbe didn’t record his death. She’ll do anything to get proof—even follow him across the ocean by joining the privateering ship, the Bluebell. But there’s a catch: the insufferable Captain, Highlander turned privateer, Xander Lock is wanted by the Crown, and a lass such as she would catch attention from the British. So, Lock has Emme disguise herself as a man. It’s fine—if she acted her way into upper class, she can act her way onto a ship— that is, until she witnesses the Cobbe commit murder. Lock explains that Cobbe has hunted him since the Battle of Culloden, and he intends to kill Cobbe for the death of his wife. She explains she needs him alive to gain the proof to access her jointure. They concoct a scheme: they’ll follow him saying they’re betrothed so they can both get what they want. Instead, with his own secrets and whispers of an island project, Cobbe traps them with an ultimatum—he’ll write a letter of proof of “death”, and as a wedding gift, stop hunting Lock—if they marry today. Emme has her proof, but a husband. Determined to hold up her end of the bargain, she accompanies Lock only to discover a love for each other they didn’t expect, despite the rocky waters of marriage. It all seems to be going swimmingly, until they learn soldiers from her late husband’s ship are missing, and all clues lead to the mysterious Oak Island. As secrets are revealed, a shocking truth threatens to destroy Lock and Emme. Now it is up to Emme to solve the mystery of Oak Island or lose the love of her life.