A boy's father is an unjustly accused fugitive, and the boy's scheming uncle plots to become the youngster's guardian and take over the family fortune.
The only key to a young woman's fortune lies in a marking on the leg of a horse called The Ghost of the Gauchos. But the woman's guardian, her uncle, plots to steal her wealth.
Helen Martin takes her father's place when he is too ill to carry out his duties as Sheriff, and followed by Jim Grey, tracks down Blackie Wells, notorious 'bad man,' who has shot up a town. The trail leads over prairie and woodland, ending when Helen assumes the part of a dancing girl in the Last Chance saloon and learns the hiding place of Blackie and his associates.
Major Carter, owner of the Sunset mines, reads of a reward offered for Cheyenne Harry if captured. The butler gives him a telegram telling of the flooding of several shafts in his mine. He is soon on the way to the mine in his car. Ruth, his daughter, follows in her roadster.
Billy Carter and two Mexicans, Cuteo and Estaban, are smugglers of opium which they bring across the border from Mexico into the United States. The authorities are unable to apprehend them, so "Pinnacle" Bill and "Cheyenne" Harry of the Arizona Ranger Service are sent to assist the sheriff, Dan Beckham, and the inspectors in their search.
John Gregg and his daughter Mary, on their way to Burro Springs, a boom mining town, lose their way and stumble into "Jawbone," a dilapidated town. Here they meet Mike Hernandez, a good-looking bad man. Mary, thinking Mike a gentleman, takes a liking to him. "Cheyenne" Harry, a homely looking good man, comes to Jawbone and Mary believes him to be a weak character. He becomes fascinated with her. Gregg hires Mike Hernandez to guide him to Burro Springs, displaying his small store of gold when paying Hernandez. Later, Gregg and his party become lost in the desert, and run out of water.
Billy Jim is a rich cowboy who tries to seduce a young girl whose father exploits a mine.
Bart Carson is in love with Lou and even goes to jail to save Walter A. Walker, a man she says is her brother but who is really a husband who has deserted his wife and two children.
An outlaw calling himself Passin' Through halts his "evil" ways long enough to help out some children in difficulty.
The Desire of the Moth is a 1917 American silent western film directed by Rupert Julian
Following his mother's death, John Gregory becomes the "Eagle," a thief determined to get even with the mining company that stole his family's fortune. Breaking into the company’s head office he discovers that another robber has preceded him and killed the night guard. When he is falsely accused, Lucy the girl he loves, discovers a written confession from the real killer just before John is to be hanged and rides wildly to the jail to save his life.
A sheep farmer brings his new wife to his father's ranch and the old man takes an instant dislike to her.
Penny arrives in the West by aeroplane. She is considered a suspicious character and thrown into jail. Kurt Walters, a ranch foreman and deputy sheriff, discovers that she is the same girl that his friend, Jo Gary, met in Chicago. Gary fell in love with her, but she confessed she was a thief. Since Penny claims she wants to reform, Walters releases her and sends her to live with Mrs. Kingdon. In spite of her teasing and taunts (or perhaps because of them), Walters finds himself falling in love with Penny.
Johnny Arthur has been ordered to spend a year out west to toughen him up, so he and butler George Davis head out. The cowboys at the ranch don't like him, so Johnny and they play practical jokes on each other. However, when Virginia Vance is kidnapped, it turns out to be real desperadoes.
Gambler "On-the Level" Leigh (William S. Hart) is forced to leave his high rolling lifestyle to move his ailing sister Alice (Mildred Harris) to the healing climate the mountains. Financial strain compels him to resume his favored vocation. Unfortunately for Level, the dance hall girl Coralie (Alma Rubens) doesn't take rejection well and convinces the dealer to clean him out with a "cold deck". A desperate robbery ensues, leading to Level wanted for murder!
Ranchmen try to play a joke on one of their associates by signing his name to a letter addressed to Sarah Smith, who has advertised in a matrimonial journal. A mix-up occurs on the day of the arrival of the lady when a younger woman, sent to buy stock, also appears on the scene and is mistaken for the prospective bride.
After the train station clerk is assaulted and left bound and gagged, then the departing train and its passengers robbed, a posse goes in hot pursuit of the fleeing bandits.
Cattlemen attempt to keep their lands and herds from being overrun by nesters.
Three Outlaws came across a stranded baby and must decide to save the child or escape from the law.
The life of Sam Houston, soldier, statesman, patriot and one of the founders of the Republic of Texas, is depicted.