Two prospectors, the fathers of Sky “Lightning” Bryce and Kate Arnold, discover a gold deposit on tribal land. They send notes to their children about their find. One father devises a plan to mark the location on a string wrapped around a dagger, with the string going to his son and the knife to the daughter if anything happens to them. That night, under the influence of a mysterious powder, Lightning’s father mistakenly kills his partner. Before dying, he gives the knife and string to the sheriff for Lightning and Kate.