Now that the miners have hit their richest vein of gold ore yet, paranormal investigators Kristin and Patrick wonder if all their mining has unleashed something powerful from deep within the notorious mine. After a harrowing encounter between the investigators and the mine's owner, Larry, the team is surprised when he organizes a cook-out for the miners and their families in a park near the town.
Larry shares the good news that the crew has officially hit their "break even" point, meaning that with just a few weeks left in the mining season, every ounce of gold from here on out is pure profit for the miners. The miners and their families enjoy a small fireworks show but as the smoke dissipates, Dingus comes to a terrifying realization: his eight year-old daughter, Marissa, is missing.
The entire camp launches into a panicked search for the little girl as the night drags on. Greybeard hears Marissa scream and finds her huddled in a small abandoned concrete shelter. She is shaken, but unharmed.
Back at the campsite, Marissa recounts what she saw and heard, describing a shadowy figure that chased her through the woods and down the road. Jamol corroborates her story by staying that he too, saw an apparition in the woods that dashed down the hill. Kristin and Patrick resign themselves for an unprepared investigation in the woods. They head to where Jamol saw something and follow the hill down where he said he saw the apparition disappear. To their surprise, the path puts them right in front of the concrete shelter where Marissa hid.
Patrick scans the hillside with the thermal camera, picking up an apparition that seems to be hiding behind a tree. When he races up the rocky hill, he finds nothing. When they reveal their footage to the miners, they are shocked, but undaunted. They believe the rise in strange activity is due to the fact that they're getting even closer to a gold mother load that the spirits may be trying to protect, only spurning them onward.
After breakfast a few days later, Kristin and Patrick return to their truck to find a mysterious note left on their windshield: "If you want to know the truth about the Crescent, call me." Dubious, Patrick dials the number. A male voice responds and agrees to meet with them, but only in a secluded, private location outside of town – alone.
As they pull up to the wooded area, Kristin worries that they should have told someone else before they left to go meet this unknown source, but it's too late: their mystery man arrives in a pickup truck. He identifies himself as Jay Phillips, a local business owner in Sumpter. He reveals that his two sons were on Larry's first crew that "tramped out" on their first expedition into the Crescent Mine after seeing and hearing shadows and disembodied voices warning them to get out of the mine. Kristin and Patrick are also shocked to learn that the Crescent Mine was owned by the Masons, a fact that Larry conveniently forgot to share with them.
Jay also reveals that there is also a strategic rock formation near the Crescent Mine that indicates the entrance to a second, secret mine owned by the Freemasons. He is unsure if the Masonic boulders are an invitation or a warning to stay away from this hidden mine.
With Stan's help, the investigators head on a Masonic scavenger hunt. On a hunch, Stan recruits his son, Eddie, to dig out the center of the formation. To everyone's surprise, they discover the remnants of an old mine entrance portal. After clearing out some debris, they are amazed to find a cleared-out mine in otherwise good condition.
They reach a wooden door sealing the rest of the way into the mine, a square and compass symbol etched into the wood that sets off their EMF detector. Eddie hacks down the door much to Kristin's dismay. They send in RIPA 2 to investigate. She stops functioning and Eddie and Stan head to the back of the mine, impatient to see what lies ahead. They are amazed to find a mine saturated with gold ore. Simultaneously, Patrick's equipment begins going off wildly.
With this new discovery, the investigators are left to wonder: just what was it the Masons were trying to hide – or keep buried away forever?
Kristen sees the opening in the side of the mountain for herself and makes a startling realization about the way the mine aligns with Baker City.
In this shocking season finale, the miners finally approach the mother lode as Patrick and Kristen reveal the final shocking pieces of the paranormal puzzle.
Stan and Eddie check in with mine owner Larry to outline their prospects for what little remains of the mining season.