To the Yukon town of Malemute and the saloon owned by "Honest John" Calhoun comes performer Belle DeValle and her troupe of entertainers. In John's absence, Belle is toasted as the "Belle of the Yukon" by saloon manager Pop Candless and his daughter Lettie, a singer at the saloon. Soon after, Sam Slade enters, looking for John and a job keeping the peace in the saloon. Sam's claim that reason is the best weapon against lawlessness is met with derision by Mervin Maitland, the dishonest town marshal. Upon returning home, John is approached by George, a swindler, about installing a crooked gambling operation at the saloon. Spouting the virtues of honesty, John refuses George and then goes to greet his new star performer. When John enters Belle's dressing room, she smashes him over the head with a vase and denounces him for ditching her in Seattle. John, who has recently changed his name to "Honest John," claims to have renounced his former life as a confidence man, but is met with skepticism by Belle, who threatens to turn him over to the Seatlle police if he is lying to her. Pop is concerned about Lettie's romantic interest in Steve Atterbury, the piano player, and sends his Indian friend, the Chief, to search Steve's room. When the Chief returns with a letter from a woman, sending her love and noting that "the children miss him," Pop becomes convinced that Steve is married and sends the letter to the Seattle police to investigate. John, who is wanted by the Seattle police, then decides to prevent the lawmen from coming to Malemute by dispatching Steve to Nome. That night, after Steve professes his love to Lettie and walks her home, several men jump from the shadows, knock him unconscious and deliver him to a riverboat bound for Nome. Unaware of Steve's mishap, Lettie informs Pop that she plans to marry him. When Pops tells Lettie that Steve is aboard the boat to Nome, Lettie thinks that she has been jilted and breaks down in tears. Not to be outwitted, Steve, meanwhile, jumps overboard and is picked up by a wagon driver, who then transports him to the trail leading to Malemute. Steve sneaks into the saloon to speak to Lettie, and is spotted by John, who sends Maitland to arrest him. The next day, John encounters Professor Salsbury on the street. The professor, an authority on weather, has been entrusted with the Alaskan weather statistics, and worried that they may fall into the wrong hands, he locks the report in John's safe. When George learns that the statistics can predict freezes and thaws, he bribes Pop to open the safe so that he can study the report. Armed with the weather forecast, George marches into the saloon, laden with bags of gold dust and offers to take bets on the date of the freeze. John, who has planned the weather scheme with the professor to fleece George of his gold, suggests that a bank be established to house all the gold dust. John is appointed bank president, but when Belle, impressed by his newfound honesty, proposes marriage, he stalls her. When Maitland complains to John about Steve's incessant demands, John suggests that the marshal get rid of his prisoner by taking him to Nome. That night, as Maitland attempts to handcuff Steve for their journey, Steve resists, and when the professor, drunk and full of remorse, begs to be locked in the cell, Steve escapes and handcuffs Maitland to the professor. Soon after, George enters the jailhouse, realizes that the professor is a swindler and hurries to the bank to withdraw his gold. There John proposes that they go into partnership and abscond with the gold when the riverboat arrives on Thursday. George agrees, and after he leaves, John reveals to Pop and Sam that he has filled the gold sacks with sand and hidden the real gold behind a stone wall. Disgusted by John's apparent dishonesty, Belle rejects him. Soon after, Maitland receives a message from the riverboat captain, asking for custody of Steve. As John and his friends search for the fugitive, Steve, disguised as a drunken Indian, slips into Lettie's room and is captured by Maitland. When the riverboat docks the next day, Steve is bidding Lettie a tearful farewell when his sister Cherie runs down the gangplank followed by his father, C. V. Atterbury. Cherie explains that she wrote the infamous letter to Steve and that the minor peccadillo he committed back home has been smoothed over by his wealthy businessman father. Freed, Steve plans to marry Lettie, and as everyone toasts the happy couple at the saloon, John is summoned to the bank and is accompanied by Pop and Sam. There the threesome are met by George and Maitland who demand the gold at gunpoint. Back at the saloon, Belle discovers that John has walked out on her act, and furious, she incites a run on the bank. Meanwhile, at the bank, Maitland demands the gold for himself, and after John peacefully hands over the bags, George, realizing that a switch has been made, locks John and his friends in the closet and extracts the bags from the wall. As an angry mob marches on the bank, John escapes from the closet, and Belle informs him that she has spread the rumor that the bank was unsafe to prevent him from absconding with the funds. Hastily pulling the real gold from a trap door, John begins to measure it out to the depositors when C. V. appears and asks to deposit $100,000 as a vote of confidence. Impressed by C. V.'s trust in John, the depositors reinvest their money, and all ends happily as Sam is appointed the new marshal, and John and Belle plan their nuptials.