Rex, a wild stallion, and Rinty, a police dog, are pals. Their master , John Sheldon, is framed for murder, and Alice Ingram plans to race Rex for money to pay for John's legal defense. Meantime, Frank Nolan, who has falsely accused John, sets out to steal Rex for himself.

A 12 episode serial starring Rex, the King of the Wild Horses and Rin-Tin-Tin, Jr. Rex is brought from the island of Sujan, where he is worshiped as a God-Horse, to the U.S. to be trained as a polo pony. He escapes, meets Rinty and with the help of Frank Bradley is returned to Sujan. The natives have been persuaded to turn against their God-Horse, however he is rescued just in time before he is burned as a sacrifice.

A young man looks for a thoroughbred horse that was got lost during a train wreck.

Rex the wonder horse's owner is murdered by Joe Regan, the leader of a band of smugglers. RCMP Sgt. Jack Gordon has been sent to capture the villain. Rex vows vengeance on Regan and helps Gordon capture him.

Jed Campbell, a "skypilot," and Nanette, a dance hall girl, meet when each goes to rescue Rex, "King of the Wild Horses," from a trap.

A stallion known as "The Black" is the leader of a band of wild horses. A cowboy is determined to capture and break him.

Columbia's King of the Wild Horses is a remake of the silent Hal Roach western feature of the same name -- and with the same "star," Rex the Wonder Horse, in the lead. Most of the story involves the romantic triangle between rogue stallion Rex, the gorgeous mare Lady, and villainous black steed Marquis.

A wild stallion (Rex the Wonder Horse) becomes the protector of a prospector and his foster daughter as two thugs plot to steal their claim.

A mysterious master criminal known as The Voice plots with his gang to sabotage the Milesburg Oil Company, but the rightful heir has a secret army of her own to protect her rights.

A cowboy and a wild horse find they have some things in common: both have enemies out to get them and both must save their mates from danger.

Jack Wade is the son of a wealthy father who runs a successful ship-building company. He uses his athletic prowess to defeat the villainous competitors who are out to financially ruin his father.

A boy's family is wiped out in an Indian massacre of a wagon train and he is captured. He befriends a wild colt. Years later, following his escape, he is recaptured by Indians who force him to fight their vicious devil horse . The horse looks somewhat familiar.

A soldier returns home from World War I with a beautiful black horse that he saved on the battlefield, and names Thunderhoof. He enters the horse in a local race, hoping to earn enough money to save the family ranch of the girl he loves. However, the crooks intent on taking the ranch manage to capture a notorious wild horse and enter it in the same race, believing that it can beat Thunderhoof and thereby ensure that they're able to take the ranch.

An unusual film in that it was composed of new film footage tacked onto an original film produced by M. H. Hoffman Sr. and Jr.,and never released because of the collapse and merger of the Hoffman's Liberty Company into the newly-formed Republic operation in mid-1935, and consequently has two different sets of actors and production crew members.

It seems that an evil saloon owner not only wants this valuable steed for himself, but also its owner, the beautiful Mary Ellis. Enter honest gambler Jack Crosby, who wants to settle the score.

Human cowboy hero is teamed with Rex, King of Wild Horses, an ornery critter but a magnificent animal.

Bud Rand, a cowboy who is charged with the care of Little Billy Rand, accepts an offer to appear with Copeland's Wild West Show to ride a horse called "Mankiller." Dude, Copeland's righthand man, resents Bud's attentions to Mary, one of the performers, and when they fight it out, Bud is the victor. In revenge Dude loosens the cinch on the horse.....

A 14-episode serial in which Mala, a Polynesian in the employ of U.S. Intelligence investigates sabotage on Clipper Island. A gang of spies causes the eruption of a volcano, for which our hero is blamed. He convinces the local Princess Melani of his innocence and helps her ward off a takeover by rival high priest Porotu.

A forest ranger comes to the aid of his fiance and her father when a crooked rancher and his gang try to force them off their land.

Purchasing the Carney Carnival and Road Show, unscrupulous sportsman Martin Trask assumes he has ownership of Rex, the world's greatest trained horse, and its rider, Margie Smith. The girl releases Rex, flees from Trask in a runaway wagon, and finds shelter with young cowboy farmer Jack Merritt, with whom she falls in love.