Herbert Corrington, a would-be gambler and agent for an express company, not satisfied with the necessities of life, tries his luck at roulette, appropriating the express company's money. Robert, the son, is fast traveling in the footsteps of his father. The Sheriff in the next county is sent for a large package of money in Corrington's possession to be delivered to the Blue Ledge Mine for the payroll. Corrington gambles a thousand dollars of this money and loses. Broncho Billy, a professional gambler, loans Corrington the money necessary to replace the funds he had maliciously taken. Corrington gives the gambler a note payable in thirty days or his home as collateral in case of default. A month later Corrington unable to meet the note ends his life. His daughter, Marguerite, and his son, Bob, are heartbroken. Broncho Billy calls to collect the money and finds Corrington's family in a terrible state. He leaves a bag of gold on the kitchen table with a note attached stating that the money enclosed is what he owed their father. Later, Marguerite and her brother are given complete charge of the express office. Like father, like son. Bob is an easy martyr to the influential gambler and loses heavily. He also appropriates money from the express office safe, and on two occasions calls on Broncho Billy for assistance. Marguerite has learned to love Broncho Billy, a professional gambler, and she promises to marry him if he will forever give up gambling. He promises. Again Bob gambles the money of his firm and loses. This time Broncho Billy is forced to try his luck at roulette in order to get the money back Bob had lost. James Spaulding, an express rider, is very fond of Marguerite and when he proposes to her, she tells him she is engaged to Broncho Billy, and unless he breaks his promise she will marry him. The express rider sees Broncho Billy gambling and he informs Marguerite, who hastily returns the ring. Broncho Billy wins and turns over the money to Bob, making him promise never to gamble again. Robert confesses his folly to his sister and tells her that Broncho Billy had gambled for him, to keep him from the penitentiary. Marguerite apologizes to the man she loves and all ends splendidly.