Everyone's after a sack of diamonds that had accidentally been dropped from an armed robber's vehicle driving through Hazzard, and all roads lead to the Duke farm after Bo and Luke get to them first. While the Duke boys are trying to report their find to the state police, they are bugged by the original thief (who poses as a reporter to get at the loot) and later, by a phony FBI agent hired by a greedy Boss Hogg who wants the reward money for himself.

Bo and Luke chase armored truck robbers through Chickasaw. But Sheriff Little mistakes the Dukes for the robbers and the only eyewitness who can vouch for them is Artie Bender - the local artist who Boss just declared legally dead so he can sell his paintings to pay off his bills.

Cale Yarborough comes to Hazzard to see a sick boy in the hospital who is about to go in for surgery. But he and the Dukes ends up getting mixed up with bank robbers.