Sadie owns a riverboat that gold-miners are using to travel to their claims, while gambling and drinking on the way. The Yukon Mining Company sends Thorne to take over Sadie's boat and then cheat the miners out of their claims. Meanwhile, Sadie has kept her life a secret from her daughter Helen, whom she has sent away to school to live a more refined life, but one day Helen arrives unexpectedly. Her naive boyfriend Bob goes to work for the dishonest Thorne, while Helen enjoys the wild Yukon more than her mother wants her to. Sadie turns to her trusted friend Ace to sort out all the complications.