American, British and Chinese secret agents battle the Japanese Black Dragon Society, a secretive ring that smuggles enemy agents into the U.S. disguised as mummies.

Foster (Charles Miller (IV)', owner of the local stagecoach line in Canyon City in the 1880s, has received a Federal Franchise Commission grant and is rushing to complete a new road through the lawless Comanche Strip with the aid of his daughter, June (Kay Aldridge), and his construction foreman "Red" Kelly (Eddie Acuff). Unbeknownst to them, their supposed friend, land-and-cattle dealer Martin Dexter (Robert Frazer), and the town lawyer, Silas Higby (Ted Adams), have plans of their own; should Foster's road see completion, homesteaders would occupy the strip and ruin Dexter's plans to buy the 500,000 acres for cattle-grazing land. Dester hires a band of renegade Indians to attack the road crew. Indian scout Jim Brady (Budd Buster)sees a supply wagon driver by "Red" and June being cased by the renegades, alerts the work-camp crew and then rides to summon Captain Duke Cameron (Allan Lane) and his U.S. Cavalry troop but, before they arrive, Foster has been killed along with many of his workmen. Cameron, a long-time friend of the Foster family, later requests his commanding officer, Colonel Andrews (Stanley Andrews) for a furlough to aid June in continuing her father's project. He then seeks to find out who is behind the renegade attack and, eleven cliffhangers later does so in the final chapter of this 12-chapter serial.

Dick Tracy goes up against a villain known as The Ghost, who can turn himself invisible.