Easterner Madeline Hammond buys a ranch not knowing Hayworth is using it to smuggle ammunition across the border. When trouble starts, she brings back Gene Stewart ex-foreman who left the country after fighting with the Sheriff.
Cowboy Ross McEwen arrives in town. He asks the banker for a loan of $2000. When the banker asks about securing a loan that large, McEwen shows him his six-gun collateral. The banker hands over the money in exchange for an I.O.U., signed "Jefferson Davis". McEwen rides out of town and catches a train, but not before being bitten by a rattler. On the train, a nurse, Miss Hollister, tends to his wound. A posse searches the train, but McEwen manages to escape notice. However a mysterious Mexican has taken note of the cowboy, and that loudmouthed brat is still nosing around. Who will be the first to claim the reward for the robber's capture?
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 and new sidekick California Carlson head to California to help out Lucky Jenkins.
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.
Stephen Westcott and Ed Martin scheme to put Jane Travers' wagon line out of business. They want to use it take over all the wagon- train traffic going west. Hoppy, California and Lucky must make sure that doesn't happen.
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.
Originally written as a stage vehicle for corpulent character actor Macklyn Arbuckle, Ernest Day's The Roundup was first filmed in 1920 with Fatty Arbuckle (no relation) in the lead. By the time the film was remade in 1941, Arbuckle's character, a roly-poly frontier sheriff named Slim (!), was refashioned as a supporting role, with Jack Benny's radio announcer Don Wilson essaying the part. The plot, however, remained fairly intact: Upon hearing that her fiance Greg (Preston Foster) has been killed, Janet (Patricia Morison) agrees to marry rancher Steve (Richard Dix) on the rebound. On the day of the wedding, who should show up but Greg, determined to raise as much Hell as humanly possible
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."
Hoppy goes undercover as a gambler from the East when Bar 20 cattle are stolen by unknown rustlers. Brennan/Talbot are twin brothers (one a casino owner, the other a rancher) and Hoppy believes they provide alibis for each other while one is out committing crimes. Hoppy gets a job in the casino to learn more but is exposed when a gambling gunslinger notices him.
Bat Masterson, who after failing to secure a job as a newspaper reporter becomes marshal of Dodge City. Preferring socializing to peacekeeping, Masterson falls in love with Dora Hand, the obligatory golden-hearted chorus girl whose concern for the welfare of her fellow citizens at time reaches Madonna-like dimensions. When Dora is shot down cattle baron King Kennedy, Masterson begins taking his job seriously. After taking care of Kennedy, Masterson determines to enshrine the memory of Dora, whose efforts to clean up Dodge City were largely ignored by the "decent" townsfolk.
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.
Belle Starr has returned from time in prison only to face a hail of bullets, along with rescue by Hoppy and the Bar 20 gang.
Ben Wade and his partner Frosty return to Bellounds' ranch where twenty years earlier Wade was wanted for murder. Unrecognized, he gets a job on the ranch and soon becomes involved in Folsom's cattle rustling and a chance to settle an old score.
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.
Buck Colins heads a group of local ranchers who are trying to prevent the railroad from completing its line through their property. Till now they have been able to charge tolls on herds passing through. Hoppy goes undercover to expose them.
Stagecoach robbers take the money Hoppy was going to use to buy cattle so Hoppy, California and Lin go after them.
Hoppy returns to find Johnny in trouble. Buck Peters has been shot by Porter who made it look like Johnny did it. When Johnny flees he runs into Linda. He takes a liking to her only to learn her father Shanghai is one of Porter's gang. Going after Shanghai, he gets captured by the gang and Porter now plans to kill him. But Hoppy is near by and Johnny will get unexpected help from Shanghai.
Richard Dix stars as Dave Morrell, the new marshal of Goliath, Oklahoma. Immediately upon arrival, Morrell finds himself at odds with banker Coy Barrett (Victor Jory), who is actually the leader of all local criminal activities.
Hopalong Cassidy and Johnny Nelson ride to the mountains to help a man and his daughter save their logging business from someone who is sabotaging their efforts.
