Jack Thornton is having problems earning enough money playing cards to cover the cost of his trip to the Alaska gold fields. His fortunes alter when he spends $250 for Buck, a sled dog who is part wolf, to protect him from being shot by an arrogant Englishman also heading for the Yukon. En way to the Yukon with Shorty Houlihan, who served time in jail for opening someone else’s letter with a map of where gold might be found, Jack saves a woman whose husband was the letter’s addressee. Buck helps Jack win a $1,000 bet so he can buy the supplies he requires. And when Jack and Claire Blake pet Buck one night, their fingers meet.