A series of deadly bank robberies involves a mysterious old lady.
A killer hides from Hoppy in a friendly Mexican town.
A black sombrero is the vital clue to a murder case.
A man suspected of murdering a businessman suffers from amnesia.
A gang tries to kill a dying murder-witness' sister.
A band of vigilantes fights a gang of stage robbers.
Bullies evict an old man from his ranch.
Hoppy tries to recover the plans of a murdered civil engineer.
A lucky prospector is the suspect for his partners' murders.
A doctor provides his outlaw brother with a phony death certificate.
Train robbers steal a relief shipment for flood victims.
A drunk fuels conflict between two tribes on an Indian reservation.
A young Mexican farmer disappears, suspected of a banker's murder.
Hoppy investigates a counterfeiting operation; Red is shot dead.
A missing man's son speaks of ghosts and strange occurrences.
Hoppy's lawyer nephew represents a bank robber.
Gold thieves frame a young friend of Hoppy's for murder.
Saboteurs try to prevent Arizona's first telegraph line.
A Gypsy seeks to clear his father of charges of robbery.
Hoppy goes to Mexico to investigate mass murders of Chinese workers.
A Southerner buys a wagon in which thieves hid money.
A banker asks Hoppy to trap robbers hijacking gold shipments.
Drought threatens cattlemen and the banker extending their credit.
Hoppy and Red resolve to help local ranchers against an exploiter who wants to take over Stone Valley and sell it to the cavalry.
Hoppy and Red are shot at in a seemingly deserted town and then discover the town's only resident was shot and left for dead.
A likable young man idolizes an infamous criminal.
A marshal accuses a brother and sister of passing counterfeit notes.
Cattlemen and sheep herders threaten to start a range war.
Hoppy helps government agents search for a herd of 625 stolen horses intended for the Spanish-American War.
Hoppy investigates a land-investment scam.
A blind woman's son, framed for murder, hides from the law.
Hoppy must locate an oil field on an Indian reservation.
Hoppy is busy tending to Red, who was injured in a fall, and helping a pretty woman hold onto her copper mine.
A saloon keeper is killed for allegedly using marked cards.
On several occasions, the same three men seem to disappear just after a robbery occurs and Hopalong Cassidy sets out to prove another man is behind the series of robberies.
A murderer frames a rancher to steal his ranch and wife.
A gang of thieves fuels resentment against successful immigrant ranchers.
A former cellmate blackmails an ex-con engaged to an heiress.
Hoppy believes a young Mexican murder suspect has been framed.
A woman marshal interferes with the efforts of Hopalong Cassidy and his sidekick Red Connors.
Ranchers are angry and suspicious when proceeds of a sale made by Hoppy wind up in the hands of a snake oil salesman.
Hopalong investigates a rash of mysterious accidents on a railroad line.
Hoppy tries to save a church from being pillaged.
Treasures interred with the dead are stolen during a scientific study of Indian burial grounds.
A wounded girl knows the way to stolen gold.
Hoppy investigates the mysterious deaths at the Last Chance Inn that are linked to one particular room.
A bank robbery ruins Hoppy's holiday in Mesa City.
Someone tries to kill California Carlson and his kin during the reading of a will.
Hoppy tracks a counterfeiting ring.
Hoppy protects a professor and his daughter from claim jumpers.
Hoppy sets out to catch a chronic breaker of saloon windows.