The team is thrilled yet concerned when the investigation of the Golden Egg, an area that scientific evidence suggests the legendary riches are hidden, immediately shows signs that they've come upon an underground void that may be collapsing.

Marty and members of the team travel to the north to a Viking settlement and uncover more evidence that may connect descendants of the Vikings to the Knights Templar. Back on Oak Island, new clues suggest Lot 5 was a place of worship.