Scooby and the gang get lost trying to cross the Canadian border and wind up at Shady Sanitarium, where Dr. Tewksbury tells them about its former owner, Dr. Coffin, whose ghost now seems to haunt the place. When the gang finds gold bullion, they suspect that something less than supernatural, and worse than unethical, is taking place. . . . The evil inventor Zorkon builds a high-test steel super skeleton for his master, Superthug, who uses it to begin a crime wave and humiliate the Blue Falcon and his mechanical sidekick, Dynomutt the Dog Wonder. After repeated failures, F.O.C.U.S. One fires the crime-fighting duo, which leaves the once heroic pair no choice but to join Superthug and his life of crime. But Superthug soon learns not to underestimate his one-time adversaries.