It's 1923 and Rocky Mountain National Park is scarcely eight years old. District Ranger Tim McIntyre is investigating the unlawful killing of three elk. Gala Book—eleven-year-old daughter of the local barber—has befriended one particularly huge bull elk and decides to protect it by leading it into the safety of the park's backcountry.

Elk are not the only endangered animals, either. While someone's killing elk to get the "whistler" ivory teeth, some Denver criminals are "harvesting" deer and elk for a political big-game supper event. Our ranger, fearing for young Gala's safety, agrees to lead the giant elk into a remote valley, only to become stranded himself. This leaves it up to his lady detective friend, Vi Coteau, to form a posse and stop the poachers. Before it's all over, McIntyre will have to engage in a deadly gunfight, and three men will be murdered.