Sergeant Preston and his great dog King have just returned to the Police post at Forty Mile after a six week patrol in the peel river district far to the north. Inspector Maynard, who was in charge of the post, listened to the Sergeant's report, then leaned back in his seat, and remembered to ask Preston about the Aurora Trading Company, who are organising a train of sleds for a freight shipment to Skagway . One of the recently recruited sled teams are rumoured to have the biggest and meanest looking lead dog - at least a foot taller than King's hefty mass!