Brothers Rick and Marty Lagina now own most of Oak Island. Determined to resurrect the 200-year-old search for treasure, they explore an abandoned shaft called 10X and use water pressure to pump material to the surface. What they find gives them reason to believe that the stories of something buried on the island may very well be true.
A scuba team that includes Marty's son Alex Lagina dives Smith's Cove and finds non-indigenous coconut fibres and anomalous stones. These findings appear to be evidence of unexplained activity in what has been conjectured to be an ancient, engineered shore area. Meanwhile, metal fragments and cat bones are found in the slurry from 10X.
As Rick and Marty Lagina begin working to drain a swamp, they are visited by a woman who lost her father and brother to a tragic accident on Oak Island that gave rise to rumours of a deadly curse.
A visitor to the island presents Rick and Marty Lagina with his theory about where the treasure on Oak Island is located and the idea that the Menorah might be among the treasures for which they are searching.
Rick and Marty Lagina find what appears to be an antique Spanish copper coin that is the first evidence of treasure on Oak Island.