Expedition Unknown (2015)

S15E4 America's First Train Robbers

Josh embarks on a quest to uncover the tale of a notorious outlaw group that wreaked havoc on the railroads of the Midwest. The Reno Gang amassed a significant fortune through their crimes, but their reign ended when a vigilante mob took matters into their own hands. Following the trail of their hidden treasure, Josh discovers a cave hideout that might conceal millions of dollars.