A mysterious disc found in the Sulphur Fork River brings a surprising outcome. Plus, other finds include weapons buried in a family’s backyard, a cryptic coin found on the Lewis and Clark Trail, and two objects that would be of great historical significance if authentic – General Custer’s rifle, and a carved clue in the disappearance of a Revolutionary War soldier.

The guys meet a man who says he can prove he has a bloodstained pistol that was owned by outlaw Jesse James. Dale visits a farmer who thinks he found proof of aliens in his own backyard. Plus, the guys try to figure out how two men discovered similar valuable objects about a hundred miles apart in the Midwest.

While Blue and Mike examine what looks like an ancient axe, Dale inspects an artifact found in a storage locker which may be tied to a brutal practice used on slaves. Plus, a wooden alligator surfaces that could link the Aborigines to America, and a man’s hand-carved pipe causes speculation on whether the U.S. was once the mythical homeland of the Aztecs.

Dale meets a man who wants to prove he found the original knife of folk hero Jim Bowie, but they get an even bigger surprise. Plus, an alleged Viking artifact found in Maine, a possible Mayan idol, and what looks like a weaponized bracelet found on a man’s land in Texas.

Dale and Blue examine whether a woman who found a letter hidden behind a picture frame stumbled on a lost piece of Abraham Lincoln correspondence that could be worth up to $1 million dollars. Mike is on a mission to connect a pair of 2,000-year-old pots found in Arkansas to conquistador Hernando de Soto. The guys also look into the value of a jade disc found in a man’s backyard, a face carving discovered on the shores of the Chesapeake Bay, and a piece of carved coral that’s a perfect match for a prized object in the British Museum.

The guys try to uncover why and how medieval scale armor was abandoned in the Arizona desert. Plus, they investigate an artifact that could connect to early Christianity, a sword found in a well, a curious clasp, and a ring found in a Los Angeles tree root whose owner thinks it could be Aztec.

Blue meets a family who found a death mask that could be evidence of a murder in the mines. Dale meets a man who thinks he has an ancient Egyptian scarab stone inscribed with a secret message, while Lily and Leonard crack the case of a mysterious object found near the Oregon Trail. Plus, the guys take to the water to figure out if corks found in the Merrimac River are tied to a valuable shipwreck.

A strange brass ball has Leonard and Blue intrigued, while Dale tries to figure out whether a man has a rare microscope owned by Thomas Jefferson. Later, Mike and Blue launch a full-scale archaeological dig at what could be the site of a lost battlefield tied to Andrew Jackson. Other finds include a strange carving pulled from a Connecticut river and a broken statue treasured by one man's father.

The guys look at two objects that may be worth big money...if they're not cursed - a bird whistle and a strange pendant with a history of preceding bad luck. Plus, the guys examine a mysterious object saved from the destruction of Hurricane Katrina, and an alleged Viking drinking horn found by a man whose wife wants to throw it out.

Lily and Dale perform tests on a gold-colored urn and soon find themselves investigating its ties to an ancient blood ritual. Meanwhile, the guys try to figure out whether a spyglass found on a mountaintop belonged to a famous explorer. Other finds include a mysterious statue, a carving found deep beneath a Dallas skyscraper, and a coin that turns out not to be a coin at all.