Hoppy goes to town to help Marshal Windy with some rustlers and winds up helping the widow Joyce when confidence men try to take her herd. King's Men songs include: "Hi Thar Stranger" and "Lazy Rolls the Rio Grande."

Caldwell and Nixon have their men rob the stage and then critcize the Sheriff for not catching the robbers. With her father the Sheriff under pressure, Mary sends for Hoppy who finds the stolen money and sets a trap to bring in the entire gang.

Escaped criminal "The Fox" hates Hoppy and a Rurales colonel for imprisoning him and lures Cassidy to Mexico in order to exact his vengeance.

Joe Weller has instigated a conflict over water rights between two ranchers. The idea is to have the ranchers do each other in then move in and take over. Hoppy and the good guys won't let this happen.

Hoppy and Lucky are headed to South America to deliver a heard of cattle. Bay guy Ralph Merritt gets in their way. For a while.

Hoppy, California and Johnny come to the ranch of a friend and his daughter, disguised as dude detectives from the east, to investigate the disappearances, without a trace, of several herds of cattle.

Hoppy and new sidekick California Carlson head to California to help out Lucky Jenkins.

A young Eastern lawyer, seriously injured in a stage holdup, secures the help of Hoppy, California and Jimmy in completing his mission to his woman cousin's ranch in Texas. The ranch, as are others in the same area, is being plagued by a gang called the Night Riders, while the friendly local town lawyer is trying to cajole the cousin into selling out to him. Hoppy begins by arriving in the town, separate from his pals, all spiffed up and dandified, posing as the Eastern lawyer...

When Ranger Hoppy's falsely accused young ranger friend is killed while supposedly trying to escape from jail, Hoppy is blamed and drummed out of the Texas Rangers.

Disguising himself as a milquetoast Easterner who writes Western novels, Hoppy enrolls in a dude ranch in order to unmask the murderer of the owner's husband.

Burton is after Clark's ranch. He gets the banker to refuse to renew Clark's note and then sends his men to rustle his cattle. Hoppy is Clark's new foreman and is on to Burton's scheme. But just as he learns of the rustling and is about to go after the gang, the Sheriff arrives and arrests him for hiding Johnny who has been accused of robbery.

U.S. Marshal Hopalong Cassidy is called when a town becomes overun with bad guys. Disguised as a member of a medicine show, Hoppy discovers that the ringleader is none other than sweet li'l ol' Ma Burton.

Hoppy, Johnny and California go to Arabia to buy some horses. There they get involved with a sheik and a harem and a kidnapping plot.

Hoppy is leading a scientific expedition and the Chinese who have a hidden settlement nearby are trying to stop them. Saulters and his outlaw gang are also in the area looking for a gold mine. When Saulters men attack, the gold mine is found. Hoppy agrees to file for the Chinese and heads after Saulters in the chase to the land office.

A crusading newspaper editor recruits his old friend Hoppy to take the job of Marshall in a town rife with vice and murder directed at helpless miners.

Hoppy, Johnny and Windy are fighting a malicious gang trying to stop a cattle drive from reaching a drought-stricken North.

As rustled cattle have mysteriously disappeared, Johnny sends for his friend Hoppy, Hoppy arrives and immediately suspects Dan Slack. Realizing his telegram about Slack was intercepted, he locks up the operator Lafe knowing he can escape. Tailing Lafe he finds a secret entrance to a mine and inside finds the missing cattle. But Slack's men also find him just as the cattle are stampeded through the mine shaft.

Posing as a cattle buyer, Hoppy crosses over into Oklahoma where the Jordan brother's and their outlaw gang operate outside the law. After receiving an unfriendly reception when he finds them, he, California, and Johnny rustle their cattle and drive across the river into Texas. He hopes they will cross over to retrieve their cattle and then he can arrest them.

A beautiful heiress is an excellent poker player. Her comfortable life changes when her father and his fortune die during market crash of the 1800's.

Hoppy goes undercover as an outlaw (which permits him, for once, to drink and be mean to children) to track down a bunch of outlaws operating along the border. Loco, the head bad guy, deflects suspicion from himself by pretending to be a moron.